How much does it take to overdose on seroquel?



Seroquel is the brand name of the generic drug quetiapine, used to treat schizophrenia and bipolar disorder (formerly known as manic-depression).

Seroquel changes the levels of neurotransmitters (naturally occurring brain substances) including serotonin and dopamine.

Seroquel belongs to a class of medications called atypical antipsychotics.

The Food and Drug Administration (FDA) approved quetiapine in 1997 under the brand name Seroquel for drug manufacturer AstraZeneca.

Two years earlier, AstraZeneca agreed to pay $520 million to settle federal investigations into the drugmaker’s marketing practices for Seroquel.

Investigators had accused the company of illegally marketing the antipsychotic drug for uses that were not approved by the FDA.

Although it’s legal for a doctor to prescribe drugs for off-label purposes, it’s illegal for a drug manufacturer to actively promote any off-label use.

Off-label uses of Seroquel include treatment of aggression, Alzheimer’s disease, anxiety, attention-deficit hyperactivity disorder (ADHD), depression, post-traumatic stress disorder (PTSD), and insomnia.

Seroquel and Weight Gain

Weight gain is a known side effect of taking Seroquel, and doctors have prescribed the drug off-label to treat anorexia nervosa.

However, a study published in European Eating Disorders Review in 2012 found that Seroquel did not help people with anorexia gain weight, nor did it help ease their symptoms of anxiety or depression.

Moreover, there is not enough evidence to show that the benefits of Seroquel for off-label uses outweigh the risks associated with the drug, concluded a study published in the Journal of Psychosocial Nursing and Mental Health Services in 2013.

Seroquel Warnings

The FDA has placed two black-box warnings on Seroquel:

First, you should not take Seroquel if you are an older person with dementia, a mental health condition that causes decreased memory, confused thinking, and changes in mood and personality.

People with dementia have an increased risk for dying while on Seroquel. If you or a family member may have dementia, talk with a doctor about this before taking Seroquel.

Secondly, Seroquel may increase your risk for suicide. The risk is greatest when starting treatment or increasing the dose of Seroquel, and may be higher for people younger than 24.

Let your doctor know right away if you are taking Seroquel and have:

  • Thoughts of suicide
  • Worsening depression
  • Symptoms of aggression
  • Irritability
  • Panic attacks
  • Extreme worry
  • Restlessness
  • Acting without thinking
  • Abnormal excitement

Your doctor will watch you carefully for any of these symptoms when you start Seroquel. Also, let your friends and family members know about these symptoms.

If you have any thoughts of suicide or if a friend or family member thinks you’re acting strangely, call your doctor right away.

Experts don’t know whether Seroquel is a safe and effective treatment for schizophrenia in children younger than 13.

The safety of the drug for treating bipolar mania in children younger than 10 and bipolar depression in children younger than 18 is also unknown.

When taking Seroquel, you should avoid extreme exercise, especially in hot weather.

Drink plenty of water, especially when you are exercising or out in hot weather.

Seroquel Withdrawal

Do not stop taking this drug suddenly, as it can cause withdrawal symptoms including nausea, vomiting, and sleep problems.

Seroquel may increase your risk for diabetes, so tell your doctor about any history of diabetes in you or your family.

Also, ask your doctor what symptoms of diabetes to look for while you are on Seroquel.

Other conditions to discuss with your doctor before you start Seroquel include:

  • Irregular heartbeat
  • History of heart attack
  • Frequent nausea or diarrhea
  • Cataracts
  • Seizures
  • High cholesterol
  • High or low blood pressure
  • History of stroke
  • History of cancer
  • Liver disease
  • Leukopenia or neutropenia (low white blood cell count)

Seroquel ‘High’ and Abuse

Doctors and drug-abuse experts have noted that Seroquel has been abused by some people for a recreational “high.”

According to a 2010 article in the journal Psychiatry, the drug goes by street names including “quell,” “Suzie-Q,” and “Q-ball.”

Though the drug may have some appeal for its ability to cause drowsiness (somnolence), abuse of Seroquel is considered very dangerous, especially when crushed and snorted.

Pregnancy and Seroquel

Seroquel is in FDA Pregnancy Category C, which means that harm to a developing fetus cannot be ruled out.

Some studies using animals have found evidence of toxic effects from taking Seroquel.

Seroquel can pass into breast milk, and the manufacturer recommends that women who are breastfeeding not use Seroquel.

In all cases, let your doctor know if you are or may become pregnant or if you are breastfeeding before taking Seroquel.

Is Seroquel Safe to Use Recreationally? (Potential Dangers)

Seroquel is the brand name for the generic drug quetiapine, which is prescribed for the treatment of symptoms associated with schizophrenia and bipolar disorder.

The drug, which belongs to the antipsychotic class of medications, works by adjusting levels of neurotransmitters like serotonin and dopamine in the brain in an effort to restore their natural balance. By stabilizing these chemicals in the brain, Seroquel users can experience mood stabilization.

The U.S. Food and Drug Administration (FDA) approved Seroquel as an antipsychotic medication in 1997. While it is not legal for pharmaceutical companies to market Seroquel for any uses other than as approved by FDA, doctors can legally prescribe Seroquel for reasons other than schizophrenia and bipolar disorder.

Additional off-label uses of Seroquel include treatment for:

  • Hostility
  • Alzheimer’s disease
  • Nervousness
  • Attention-deficit hyperactivity disorder (ADHD)
  • Persistent depression
  • Post-traumatic stress disorder
  • Sleeplessness

Side Effects

Both positive and negative side effects are commonly observed with Seroquel use. There are various intended benefits of Seroquel, which include:

  • Improved concentration
  • Decreased hallucinations
  • Increased energy
  • Increased positive mood
  • Decreased occurrence and severity of dramatic mood swings

Common negative side effects of Seroquel include:

  • Low blood pressure
  • Dizziness
  • Increased heart rate
  • Fatigue
  • Sedation
  • Dry mouth
  • Agitation
  • Increased appetite
  • Constipation

It is rare to experience side effects that are more serious than the ones listed above, but it is possible. Though uncommon, these serious side effects are possible with long-term use of Seroquel:

  • Loss of period in females
  • Erectile dysfunction in men
  • Decrease in sex drive
  • Osteoporosis
  • Restlessness, tremors, and muscle stiffness
  • Uncontrollable slow or jerky muscle movements
  • Weight gain
  • High blood pressure
  • High cholesterol
  • Diabetes

Some of symptoms listed above can increase your chances of cardiac problems, stroke, and death, so it is important to keep your doctor informed of the development of any concerning side effects. Your doctor can determine whether the intended benefits of Seroquel continue to outweigh any side effects you may be experiencing and if it’s appropriate to keep you on the mediation.

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Why Do People Use Seroquel Recreationally?

People report using Seroquel recreationally for the high it can produce. When taken in high enough doses, some people can experience a relaxing high that helps them slow down. Some people even use it for the extreme drowsiness it can cause.

It can be taken orally, intranasally, or intravenously.

People who report recreational use of atypical antipsychotic medications like Seroquel say the drug helps them enhance the effects of other substances or recover from the adverse side effects of drinking alcohol. Pure experimentation is a reason some people use Seroquel recreationally and with other substances.

While Seroquel can be legally be obtained through a doctor’s prescription, it is not difficult for people to get the drug for recreational purposes. People may convince a doctor that they need it, receive multiple prescriptions at once from different doctors, get the drug from family or friends who were legally prescribed it, or buy it illegally off the street.

Potential Dangers of Recreational Use

Recreational use of Seroquel is risky, as there are potential dangers associated with experimenting with it. Seroquel use is considered to be especially dangerous for people who crush and snort the drug.

The National Alliance on Mental Illness (NAMI) explains that the FDA has given at least two black box warnings to Seroquel. One warning is for elderly patients who are already diagnosed with dementia-related psychosis. Antipsychotic medications like Seroquel are associated with increased rates of death for this population.

The second black box warning discusses the potential for suicidal thoughts or attempts in children and adults taking Seroquel. People with a history of mental illness, particularly depression, have reported experiencing an increase in the severity of their depression as well as the occurrence of suicidal ideation.

Those with a history of substance misuse often present with co-occurring mental health issues. Anyone experimenting with Seroquel for recreational reasons must be very cautious and aware of the development of any thoughts of suicide or worsening depression. Such thoughts need to be addressed right away by medical professionals to ensure symptoms do not worsen or become fatal.

In addition to the risk of ignoring the black box warnings of Seroquel, recreational Seroquel users are likely to be polysubstance users. Polysubstance abuse refers to using at least three different types of substances, which is a practice that is very dangerous for physical and mental health. It is difficult to anticipate how substances will interact with one another.

In the case of mixing Seroquel with other drugs, studies have found that most people who abuse antipsychotic medications misuse other drugs, as well. Atypical antipsychotics are most commonly reported to be mixed with alcohol, opioids, and cocaine. Often, many of these substances are used in combination.

Is Seroquel Addictive?

Seroquel is not considered to be addictive because it does not have the same effects on a person that addictive drugs do. Some people may abuse Seroquel for its sedative effects or in hopes of managing other symptoms, but it does not produce the euphoric high that people become addicted to. No clear behavioral reward encourages use.

In general, antipsychotic medications are not addictive. They do not produce a euphoric high, create a desire in people to continuing using the drug, or foster a need to consume increasingly greater quantities of the drug. Despite this, people do use the drug recreationally.
While antipsychotic medications are generally accepted to not be addictive, withdrawal symptoms can appear when you stop taking them.

The occurrence of withdrawal symptoms when you stop taking a drug does not equate to addiction, though it does indicate that your body has developed a physical dependence on the drug. In the case of antipsychotic medications, you may experience nausea, vomiting, diarrhea, stomach pain, dizziness, and shakiness when you stop using them.

To avoid uncomfortable withdrawal symptoms, doctors do not recommend quitting Seroquel all at once. They will help you make a plan to slowly reduce your intake of the drug over some weeks.

If you have been taking Seroquel for medical reasons, quitting all at once puts you at risk for psychotic symptoms returning or getting worse.

How to Use Seroquel Without Abusing It

The best way to use Seroquel without abusing it is by limiting your use to purely medical purposes and only as directed by your doctor. While antipsychotic medications are not addictive, recreational use of any substance is still risky.

Particularly if you are mixing Seroquel with other substances, you are exposing yourself to potentially severe and dangerous side effects. As with all prescription medications, there is no safe way to use Seroquel recreationally.

Polysubstance Dependence. Encyclopedia of Mental Disorders. Retrieved January 2019 from

Intoxication after Extreme Oral Overdose of Quetiapine to Attempt Suicide: Pharmacological Concerns of Side Effects


Quetiapine is an atypical antipsychotic approved for the treatment of patients with psychotic disorders. Since approvement several case reports about intoxication with quetiapine were linked mainly with tachycardia, -prolongation, somnolence, and hyperglycemia. Here, we present the first case report of an intoxication with an extreme overdose of quetiapine (36 g), ingested by a 32-year-old female (62 kg bodyweight) to attempt suicide. Symptoms associated with intoxication were coma without arterial hypotension, persistent tachycardia, hyperglycemia, and transient hypothyreoidism. -interval was moderately extended. Management consisted of intubation for airway protection, gastric lavage, the use of activated charcoal, i.v. saline, and observation for 17 hours on an intensive care unit. Despite the extremely high dose of quetiapine, the patient recovered completely without residual symptoms.

1. Introduction

Quetiapine is indicated and approved for the treatment of psychotic disorders in adults by the U.S. Food and Drug Administration. The efficacy of quetiapine in the treatment of acute mania and depression associated with bipolar disorder and the therapy of schizophrenia with quetiapine has been proved in randomized controlled trials (for review, see ).

Pharmacokinetics and pharmacodynamics of quetiapine fumarate (Seroquel), a dibenzothiazepine antipsychotic agent bearing structural similarity to clozapine and olanzapine, have previously been described and reviewed . After oral administration the drug is eliminated with a mean terminal half-life of approximately 7 hours . The volume of distribution and total protein binding is 10 l/kg and 83%, respectively (Prod. Info Seroquel, 2004a). The drug is primarily metabolized by sulfoxidation and oxidation with the CYP3A4 isoenzyme and the 7-hydroxylated as well as the N-dealkylated metabolite are pharmacologically active .

Quetiapine shows affinity for multiple neurotransmitter receptors in in vitro binding studies. The drug exhibits high affinity for serotonergic 5-H -receptors and moderate affinity for dopamine D2-receptors; whereas antagonism of D1- and 5-H -receptors is relatively weak. The antipsychotic effect is explained by the antagonistic effect on D2-receptors and 5-H -receptors .

Appreciable affinity for -adrenergic, -adrenergic, and histamine H1-receptors has also been observed .

Adverse effects even at the beginning of the therapy like sedation and somnolence are explained by antagonism of histamine H1-receptors. Orthostatic dysregulation, hypotension, and tachycardia are associated with an antagonistic effect on -adrenergic receptors. Quetiapine has also been reported to have an antagonistic effect on M1-muscarinic receptors resulting in anticholinergic mediated tachycardia .

Quetiapine and other atypical antipsychotic drugs like clozapine or olanzapine provide antipsychotic efficacy with a lower risk of EPS compared to typical antipsychotics, but atypical antipsychotics are associated with a variety of metabolic and cardiovascular adverse effects particularly with regard to an overdose . If treating patients with quetiapine one should be familiar with the clinical symptoms of quetiapine intoxication and its treatment. Here, we report on clinical effects of an extreme quetiapine overdose and how such an intoxication can be survived under appropriate treatment.

2. Case Report

We report on a 32-year-old female (62 kg bodyweight) with history of paranoid-hallucinatory schizophrenia and depression who was discovered by her companion in life 26 hours after ingestion of 36 g quetiapine (120 tablets of 100 mg and 80 tablets of 300 mg) and a suspected abuse of lorazepam. A previous suicide had been attempted 10 years before with haloperidol. Her past medical history was negative for cardiac dysrhythmia, hypertensive heart disease or a thyroid dysfunction. The emergency medical service found the patient comatose with response only to deep painful stimuli (Glasgow Coma Scale of 9), normotensive (127/83 mmHg), hyperglycemic capillary glucose level: 8.96 mmol/L  = 160 mg/dl and tachycardiac with sinustachycardia of 140 bpm, capillary oxygen saturation was 98% and respiratory rate 12/min. There was no evidence of trauma or infection. During the transport to the hospital 40 mg of furosemide and 1000 mL saline were administered intravenously for detoxification and prophylaxis of hypotension. Vital signs were stable during transport.

To prevent her from further absorption of quetiapine a gastric lavage was performed (no pill fragments of ingested tablets were recovered) and the patient enterally received 25 g of activated charcoal with 5 g Glauber’s salt (sodium sulfate) every 3 to 4 hours until dejection of black stool.

Laboratory data on admission including serum electrolytes, liver, and renal function parameters and blood count remained normal except glucose of 8.12 mmol/L (145 mg/dl), CK of 333 U/L (control value remained unchanged) with no evidence of myocardial insufficiency or infarction, CRP of 32 mg/L (control value 8 hours later increased to 76 mg/L), TSH 6.0 mU/L (control value 8 hours later increased to 8.56 mU/L), and leucocytosis with 12.06 ( /L).

The electrocardiogram at 36 hours postingestion revealed a moderately extended interval measuring 436 millisseconds (at the upper limit of normal) compared to interval of 388 ms after complete recovery. -intervals were calculated using the Bazett formula .

A comprehensive drug screen via immunoassay was positive for tricyclic antidepressants and benzodiazepines in particular, although these results could not be confirmed by UV-HPLC-methods.

One day after admission cardiac and pulmonary status was stable (without signs of -prolongation, arrhythmia, or tachycardia), state of consciousness improved, so that she could be extubated and was transferred to psychiatric crisis ward within 67 hours after ingestion of quetiapine. The increased levels for glucose and TSH lasted for 2.5 days, CK turned to normal after 6 days and CRP after roughly two weeks, respectively (see Table 1).

Table 1
Figure 1
Serum time-concentration profile of quetiapine after ingestion of an assumed amount of 36 g Seroquel in a 32-year-old female patient. Solid-line: fitted line based on a two-compartment model assuming a reduced resorption. Dotted line: fitted line expected by population pharmacokinetic parameters and normal resorption.

Serum-samples for pharmacokinetic analysis were collected directly on arrival in the emergency department, 5 hours after admission and the following two days (four samples in total). Quetiapine serum concentrations were determined by a validated UV-HPLC-method (linearity range 0.03–4.00 mg/L, lower limit of quantification (LLOQ) 0.03 mg/L, limit of detection (LOD) 0.01 mg/L). Drug concentrations and patient’s data (gender, age, weight, height) as well as the ingested amount of quetiapine were processed by a commonly used pharmacokinetic program Mw/Pharm 3.50 . Pharmacokinetic parameters were investigated based on an open two-compartment model and a Bayesian fitting procedure.

Elimination half-life was calculated as follows:

− (elimination, is the rate constant corresponding to the terminal elimination).

Figure 1 exemplifies the obtained quetiapine concentration levels and the software generated time-concentration profile based on a two-compartment model (solid-line). In addition, the expected time-concentration profile based on population-pharmacokinetic data is shown (dotted line). Absorption was supposed to be reduced because of anticholinergic effects of quetiapine on intestinal tract.

The elimination half-life was hours and was calculated based on the four obtained quetiapine concentration levels (c1  = 4.22 mg/L; c2  = 2.77 mg/L; c3  = 0.06 mg/L; c4  = 0.06 mg/L) with regard to patient’s medical records and displayed a moderately increased elimination compared to population pharmacokinetic parameters. Additionally, the absorption rate constant (time)-1 had to be adjusted and displayed a reduced absorption of quetiapine after ingestion. In this case the patient was supposed to have ingested 36 g quetiapine corresponding to a dosage of 580 mg/kg quetiapine. Volume of distribution was within the expected range (  L/kg based on fitted solid line, Figure 1).

Expected peak quetiapine concentrations for population-pharmacokinetic data were higher than the fitted time-concentration profile based on measured quetiapine concentrations and a two-compartment model.

3. Discussion

This is the first case report of an intoxication with such an extremely high amount of quetiapine (580 mg/kg). Remarkable side effects were tachycardia, somnolence, hyperglycemia, transient hypothyroidism, and a moderately prolonged -interval, but the patient survived and fully recovered.

Side effects: tachycardia is most likely explained by an anticholinergic effect of quetiapine .

Symptoms of central nervous depression (somnolence, drowsiness) are primarly mediated through antagonistic effect of quetiapine on serotonergic 5-H – and moderate antagonistic effect on dopamine type 2 D2-receptors. Prolonged tachycardia is usually explained by an antagonistic effect of quetiapine on -receptors . Generally, the adverse effects like tachycardia, hyotension, and somnolence associated with quetiapine in particular after ingestion of an overdose can be explained by blockage of the alpha-adrenergic, muscarinic, and histamine receptors .

In recent publications surprisingly no statement about additional blood glucose laboratory data was provided, although several case reports after ingestion of high dosages of quetiapine were presented .

The mechanism for hyperglycemia may be related to 5-HT2-receptor antagonism, which is associated not only with weight gain but also with hyperglycemia . 5-HT2-receptor antagonists can significantly decrease insulin sensitivity, an effect possibly mediated by the suppression of 5-H -receptor-mediated glucose uptake in skletal muscle . For instance, 5-H knockout mice develop insulin resistance and impaired glucose tolerance and show severe weight gain . This may be a likely mechanism for hyperglycemia in the therapy with atypical antipsychotics and in case of quetiapine overdose.

Moreover antipsychotic drug affinity and antagonistic effects on muscarinic receptors are significant predictors of the development of diabetes. Muscarinic M3-receptors are highly expressed by pancreatic -cells and antagonism leads to dysregulation of glucose-dependent acetylcholin modulation of insulin secretion .

Suppression of compensatory insulin release may explain hyperglycemia in the present case report of quetiapine overdose.

Summarized, three receptor mediated mechanisms are commonly supposed for glucosedysregulation in particular after intoxication with an atypical antipsychotic.

First, 5-H -receptor antagonism: suppression of receptor-mediated glucose uptake in skeletal muscle.

Second, 5-H -antagonism is correlated with an increased risk of diabetes and weight gain most likely explained by 5-H -receptor mediated insulin resistence and impaired glucose tolerance .

Third, M3-receptor-antagonism: dysregulation of glucose-dependent acetylcholin modulation of insulin secretion.

Hypothyroidism associated with quetiapine treatment has been reported in previous studies under treatment with a normal daily dosage of quetiapine . Although the mechanism is not known a competitive metabolism of thyroid hormones and quetiapine by UDP-glucoronyltransferase has been suggested as a plausible mechanism for a decrease of thyroid hormones during quetiapine treatment .

In case of a patient with compromised thyroid function receiving treatment with quetiapine may develop hypothyroidism and clinicians should consider routine monitoring of thyroid function .

Observed Quetiapine Concentrations and Pharmacokinetics. In our case report the measured serum concentrations of quetiapine were lower than the expected quetiapine concentrations due to the absorption rate constant, (time)-1 and displayed a reduced absorption of quetiapine after ingestion (Figure 1). These findings are consistent with previously findings . Lower than expected peak concentrations may be explained by potential anticholinergic effects of quetiapine reducing absorption. With regard to a delayed absorption the expected time to maximum quetiapine concentration is supposed to be prolonged in these cases. In contrast to the findings of Hunfeld et al. we determined a serum time-concentration profile lower than the expected one. We assume that the impacts of side effects after ingestion of a very high amount of quetiapine may have contributed a decreased absorption with no influence on terminal elimination half-life.

With regards to the rescue case protocol the patient is supposed to have ingested 36 g quetiapine (rescue operation record: 120 tablets of 100 mg and 80 tablets of 300 mg). Although it cannot be ruled out that the ingested amount might have been less than 36 g, the time-concentration profile in this case is based on reduced absorption.

In contrast to these explanations the reason for considerably lower than expected quetiapine concentrations could obviously be an ingestion of a much lower amount of about 18 g quetiapine.

A comprehensive drug screen via immunoassay was positive for tricyclic antidepressants and benzodiazepines in particular.

Though an additional spectrophotometric (UV)-HPLC-method performed by the institute of forensic medicine did not confirm the concomitant intake of lorazepam.

Drug screening also was positive for tricyclic antidepressants, although the use of immunoassays is limited, because different drugs of the corresponding group may have quite different cross reactivity and/or pharmacological potency .

A comprehensive drug screening of tricyclic antidepressants could not be confirmed in additional analyses with UV-HPLC.

Recommendations for Management of Therapy after Quetiapine Intoxication. The treatment of quetiapine intoxications in case of an unknown ingested amount in particular consists in a supportive therapy and the patients should be monitored in an intensive care unit.

Forced Diuresis with Furosemide and Saline. Although 40 mg furosemide were administered during transport, the treatment with diuretic drugs for the purpose of enhanced elimination is no longer recommended . Moreover the efficiency of this treatment is limited due to a relatively large volume of distribution of quetiapine (  l/kg) and a small renal elimination rate of quetiapine (less than 5%).

In case of a hypotensive patient the administration of diuretic drugs (e.g., furosemide) is not recommended, because of worsening the patients condition (further decrease of blood pressure).

Gastric Lavage after 27 Hours. To prevent further absorption of quetiapine a gastric lavage was performed and the patient was given activated charcoal with Glauber’s salt 27 hours after quetiapine ingestion according to the recommendation of Burns et al.

At this time gastrointestinal passage of quetiapine is almost completed, although charcoal and glauber’s salt (sodium sulfate) should be administered as soon as possible, if lag-time of drug ingestion is unknown. It should be noted that the risk of death following atypical antipsychotic overdose is very low and gastric lavage is not routinely recommended after the 60 minutes time range .

Monitoring of cardiac and respiratory function, intravenous access, and a 12-lead ECG is required .

Adminstration of intravenous magnesium sulfate (2 g bolus followed by an infusion of 2–4 mg/minute) is the intial therapy of choice regardless of serum magnesium level to the patient with prolongation. Serum potassium should be maintained in the high-normal range (4.5–5 mmol/L) and ingested drugs as well as interfering drugs with its metabolism have to be discontinued .

Monitoring of thyroid function in quetiapine treated patients with a history of or a vulnerability to thyroid disease is strongly recommended .

4. Summary

To our knowledge, the present case report is the first with an extremely high ingestion of quetiapine (36 g). Symptoms associated with intoxication were coma without arterial hypotension, persistent tachycardia, hyperglycemia, transient hypothyroidism, and a moderately extended -interval. Management of overdose consisted in primarily supportive therapy on an intensive care unit.

In addition the present case may help us to understand the different side effects of an atypical antipsychotic drug with regard to receptor-pharmacological mechanisms.

Therapeutic drug monitoring and pharmacokinetic analysis of quetiapine after intoxication displayed a moderately increased elimination and a reduced absorption of quetiapine.

Despite the extreme overdose of quetiapine the patient exhibited a rapid clinical improvement and recovered without residual symptoms.



Ms. M. was a 23-year-old graduate with no family or past history of significant medical or psychiatric illness. Her psychiatric illness of insidious onset and continuous course of 3 years was characterized by muttering and laughing to self, and undressing in public without reason, social withdrawal, irritability and anger outbursts, delusions of reference and persecution, and auditory hallucinations of commanding type; but no significant affective or cognitive symptoms. Two years back for no reason but with a serious suicidal intent she had consumed toilet-cleansing liquid without any medical sequel. Since then she was under psychiatric treatment, which included 5 ECTs, and for the last 9 months tablets quetiapine 400 mg, chlorpromazine 150 mg, risperidone 4 mg and clonazepam 2 mg daily; with partial improvement (GAF score-30) despite good compliance ensured by the family.

Following an anger outburst she consumed 14 tablets of quetiapine 100 mg and within one hour she was brought to our emergency services. There was no history of any other concurrent drug overdose. Physical examination was normal except for drowsiness and tachycardia (140/minute); there was no respiratory depression. Mental status examination showed good orientation, commanding auditory hallucinations, marked hostility, and anger outbursts. She gave no reason for the overdose. Routine hematology, biochemistry, and chest x-ray were normal; ECG showed supraventricular tachycardia (167/minute) and minimal ST depression in leads V1 to V6. Gastric lavage was done within 2 hours of overdose; lorazepam 2 mg i/v was used once to control agitation. After 14-hour observation in emergency she was sent home.

The next day at psychiatric outpatient follow-up quetiapine was increased to 600 mg daily (risperidone and clonazepam were not prescribed). Three weeks later another suicidal attempt by wrist slashing forced her admission to the psychiatry ward. A repeat ECG showed supraventricular tachycardia (152/minute); there were no other cardiac symptoms/signs, and hematology and biochemistry were all normal. The cardiologist opined ‘medication-side-effect’ and advised no active intervention. The tachycardia subsided over the next one week. With no improvement with over 8 weeks of quetiapine 600 mg daily, 9 alternate-day ECTs were given. Lack of further improvement and her past best response to quetiapine-risperidone combination led to re-induction of risperidone, increased over 3 weeks to 6 mg/day. Non-pharmacological measures (activity scheduling, reinforcement regime/token economy) were also added. Over the next 9 weeks she showed significant improvement, to GAF score of 76. Overall, her recovery from overdose was uneventful and did not adversely affect reinstitution of quetiapine or risperidone and successful plastic surgery for repair of median nerve, damaged during wrist slashing. With good treatment compliance for the last one and a half year she has maintained her improvement. During follow up 4 weeks back her cardiac examination and repeat ECG showed no abnormality except for sinus tachycardia (100/minute).

What Does a Seroquel Overdose Look Like? How to Help

Seroquel is an antipsychotic medication that might be prescribed for schizophrenia and other mental health disorders. It changes the neurotransmitters in the brain to treat these conditions. It can have a calming effect, and this is the primary reason people abuse the drug.
Some people might use Seroquel alone to relax while others will take it to reduce the effects of stimulants they have used. In some cases, Seroquel is combined with stimulants.

How to Recognize a Seroquel Overdose?

A Seroquel overdose can be a potentially life-threatening issue. It is important that all people who are around this drug know how to recognize an overdose. Quick treatment for the overdose is necessary to reduce the risk of further issues for the person experiencing the overdose.
If someone takes too much Seroquel at one time, they are at risk for an overdose. Possible symptoms of an overdose, according to Dr. Chris Iliades, M.D., include:

  • Rapid heartbeat
  • Dizziness
  • Vomiting
  • Fainting
  • Drowsiness
  • Seizure

Dangers of an Overdose

A person can overdose on Seroquel when they take it alone or with other drugs. When an overdose happens, the person’s body can’t handle the amount of the drug present. This is what causes the typical overdose symptoms. However, other possible issues can occur as the result of an overdose.

It is possible for someone to experience a coma due to an overdose. When this happens, it is impossible to predict whether the person will wake from the coma. If they do wake up, there is the potential for additional complications, especially if the coma lasts a long time.

Other possible dangers of a Seroquel overdose include respiratory depression, high blood sugar, seizure, and low blood pressure. Compared to all other antipsychotic drugs, coma, hypotension, and respiratory depression appear to be more common with a Seroquel overdose, according to research published in the Annals of Emergency Medicine.

When someone has a Seroquel overdose, seizures are possible. On average, seizures last about 30 seconds to 120 seconds, according to the Mayo Clinic. When a seizure occurs, the person experiencing it can fall and experience an injury. In more severe cases, injuries may include a head injury, broken bone, or severe laceration.

Respiratory depression is characterized by a person’s breathing being ineffective and slow. This can reduce the amount of oxygen the brain and other organs receive. When someone isn’t breathing properly, it can also result in carbon dioxide accumulating in the body.

Low blood pressure can result in blood not being pumped efficiently throughout the body. When this issue is present, there is a risk of shock, which means the body’s organs are not getting enough oxygen, according to the National Heart, Lung, and Blood Institute. This can cause an array of problems, such as a loss of consciousness and confusion.

Hyperglycemia means a person’s blood sugar is too high. Should this problem persist for a long time, the person will be at risk of damage to the blood vessels, nerves, and other organs, according to the Cleveland Clinic. If the person’s blood sugar gets high enough, there is a risk for a hyperglycemic hyperosmolar state or ketoacidosis. These complications are typically only seen in people who have diabetes.

What Can Cause a Seroquel Overdose?

People can overdose on Seroquel. There have been incidences of fatal overdose that included this drug alone or in association with other drugs or medications. Once someone takes this drug, the gastrointestinal tract absorbs it. Peak plasma levels occur within about two hours when someone takes this drug orally, according to information published in the Journal of Analytical Toxicology.

No single dose will be fatal to all people. Several factors can play a role, such as a person’s overall health, if they are using other drugs or medications, their overall size, and how long they have been taking Seroquel.

Information published by Dr. Ed Burns states that Seroquel doses that exceed 3 grams may result in coma. Some people may experience an overdose with smaller doses.

A fatal overdose was noted when someone ingested 13.6 grams of this medication, according to Dr. Chris Iliades, M.D. The adult dosage for this medication ranges from 150 mg (milligrams) to 800 mg per day, depending on the condition being treated.

Any person who uses the drug recreationally is at risk of an overdose. This risk increases if someone crushes, breaks, or chews an extended-release tablet. Using this drug via injection, smoking, or snorting can also increase the risk of an overdose since these methods make it more difficult to dose accurately.

How to Help Someone Who Is Overdosing on Seroquel

If someone overdoses on Seroquel, they need immediate medical attention, so call 911 right away. When talking to an emergency dispatcher, it is important to provide them with as much information as possible about the person and situation such as:

  • The person’s overall size and age
  • The drug they took and the dosage, if known
  • Any other drugs, supplements, or medications the person has taken recently
  • Any health issues the person might have

If the person is not breathing, providing rescue breaths is important. For those who do not know how to do this, the 911 operator may walk them through it. They can also walk people through performing CPR if this becomes necessary.

If the person can breathe, they should be turned on their side and supported so that they do not fall onto their back. By turning the person on this side, it will reduce the risk of aspiration. If someone is lying on their back and they vomit, they can breathe this into their lungs or choke.
If the person breathes in some vomit, it puts them at risk for aspiration pneumonia. In the most serious of cases, this may cause the following, according to MedlinePlus:

  • Lung abscess
  • Bloodstream infection if pneumonia spreads
  • Respiratory failure
  • Shock
  • Death

It is imperative not to leave someone alone when they are experiencing an overdose. The person may need to be monitored until emergency help arrives to take over.

A Seroquel overdose is a serious matter. Any person who has overdosed on this drug needs professional addiction treatment. Stopping abuse of this drug and all other illicit substances is the only way to prevent another overdose.

Aspiration Pneumonia. MedlinePlus. Retrieved January 2019 from

Quetiapine, the antipsychotic ‘sleeping pill’ linked to overdoses

Quetiapine is increasingly prescribed a sleeping drug. Credit: Mink Mingle

Quetiapine is a drug designed to reduce hallucinations and delusions experienced by people with schizophrenia or bipolar disorder.

The most common brand name of quetiapine is Seroquel but it’s also known by the slang names quell, Suzi-Q, baby heroin and Q-ball. Q-ball refers to a combination of quetiapine and cocaine, or sometimes heroin.

Quetiapine was developed by the ICI chemical company in England and patented in 1987. Scientists were trying to find a drug that would help reduce the symptoms of mental illnesses without the distressing side effects caused by the antipsychotics developed in the 1950s.

How does it work?

Quetiapine works by attaching to the brain’s dopamine receptors and altering serotonin levels.

Short-term effects include feeling sleepy, a dry mouth, dizziness and low blood pressure when you stand up. These effects lasts about six hours.

The product information for quetiapine includes a warning not to drink grapefruit juice while taking the medication because it stops the drug being metabolised in the intestines and could increase the effects of the drug.

Longer-term effects of quetiapine use include weight gain, high blood sugars and a greater risk of diabetes.

People who take quetiapine regularly will experience withdrawal when they stop. Symptoms include nausea, insomnia, headache, diarrhoea, vomiting, dizziness and irritability.

Use as a sleeping drug

Quetiapine is often prescribed by doctors at low doses for things other than mental illness. This is mostly because the main side effect of it is making people feel sleepy.

As doctors have realised that benzodiazepines cause dependence when used regularly, other options to help people sleep or calm down have been sought and quetiapine has filled the gap.

Doctors report prescribing quetiapine because they were not sure about a patient’s mental health or they had a lot of personal problems.

War veterans are a group who have found quetiapine useful for sleeping. Soldiers first using it reported relief from nightmares and anxiety. Some said it was the first time since returning home from war that they had more than six hours sleep.

However, several deaths related to quetiapine were reported in the United States.

Concerns have also been expressed about prescribing quetiapine to Australian soldiers with post-traumatic stress disorder (PTSD) instead of providing talking therapies.

Recreational use

The reasons people use quetiapine recreationally are the same as for other drugs, for example, they like the effect, it enhances the effect of other drugs, or they want to experiment.

Other uses include managing the symptoms of withdrawal from other drugs, including helping with sleep.

Drug information websites describe quetiapine as good for the “comedown” because it puts people to sleep very quickly.

People using amphetamines can regularly experience psychotic symptoms. Quetiapine has been recommended around networks of people who use drugs as helpful way to reduce those symptoms.

Rising popularity

Since 1997 when quetiapine was approved in the US, prescribing rates have increased dramatically all over the world. It’s the fifth-biggest selling prescription drug in the US, with sales over US$6 billion.

In Norway, prescriptions for quetiapine have increased over time from 584 in 2004 to 8,506 in 2015.

In 2010, AstraZeneca – the US pharmaceutical company that makes Seroquel – was fined US$520 million for promoting “off-label” uses of Seroquel to doctors.

This means it was promoted for conditions it was not licensed to treat, such as anger management, anxiety, attention-deficit hyperactivity disorder (ADHD), dementia, depression, mood disorder, PTSD, and sleeplessness.

The company denied the allegations but had to pay the fine.

Overdose and dependence

As prescribing of quetiapine has increased, so have reports of overdose and problems with dependence on the drug.

A study of ambulance call outs in Victoria found substantial increases in the number of calls for quetiapine overdoses and that most overdoses are in areas with high prescribing rates.

The United States Drug Abuse Warning Network reported a 90% increase in quetiapine-related emergency department visits between 2005 and 2011. The people most at risk of overdose were those using other drugs and women.

Men in their mid-thirties are the largest group of non-medical quetiapine users but it’s also common among some teens. A NSW Justice Health report found that 16% of 14- and 15-year-olds in juvenile justice centres had used quetiapine they weren’t prescribed.

Studies of quetiapine misuse have found most people are using other drugs as well – mostly benzodiazapienes or prescription opioids.

A study of people in a substance treatment program found 96% of people had used quetiapine, which they got from doctors or family and friends.

Explore further

What is Seroquel and should you take it for insomnia? Provided by The Conversation

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Citation: Quetiapine, the antipsychotic ‘sleeping pill’ linked to overdoses (2018, November 7) retrieved 2 February 2020 from This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.


Before taking quetiapine,

  • tell your doctor and pharmacist if you are allergic to quetiapine, any other medications. or any of the ingredients in quetiapine tablets or extended-release tablets. Ask your doctor or pharmacist or check the Medication Guide for a list of the ingredients.
  • tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements and herbal products you are taking or plan to take. Be sure to mention any of the following: antidepressants; certain antifungals such as fluconazole (Diflucan), itraconazole (Sporanox), ketoconazole (Nizoral), and voriconazole (Vfend); antihistamines; barbiturates such as phenobarbital; carbamazepine (Tegretol); chlorpromazine; divalproex (Depakote); certain medications for irregular heartbeat such as amiodarone (Cordarone), procainamide, quinidine, and sotalol (Betapace, Betapace AF, Sorine); dopamine agonists such as bromocriptine (Parlodel), cabergoline (Dostinex), levodopa (Dopar, Larodopa), pergolide (Permax), and ropinirole (Requip); erythromycin (E.E.S., E-Mycin, Erythrocin); gatifloxacin (Zymar, Zymaxid); levodopa (in Parcopa, in Sinemet, in Stalevo); levomethadyl acetate (Orlaam) (not available in the U.S.), medications for anxiety, high blood pressure, irritable bowel disease, mental illness, motion sickness, Parkinson’s disease, ulcers, or urinary problems; medications for human immunodeficiency virus (HIV) such as indinavir (Crixivan), nelfinavir (Viracept), ritonavir (Norvir, in Kaletra), and saquinavir (Invirase); methadone (Dolophine, Methadose); moxifloxacin (Avelox, Moxeza, Vigamox); pentamidine (Nebupent, Pentam); phenytoin (Dilantin); rifampin (Rifadin, Rimactane); sedatives; oral steroids such as dexamethasone (Decadron, Dexone), methylprednisolone (Medrol), and prednisone (Deltasone); sleeping pills; thioridazine (Mellaril); tranquilizers; and ziprasidone (Geodon). Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • tell your doctor if you or anyone in your family has or has ever had diabetes or a prolonged QT interval (a rare heart problem that may cause irregular heartbeat, fainting, or sudden death). Also tell your doctor if you have ever used street drugs or overused prescription medications, if you have severe nausea or diarrhea, hypokalemia or hypomagnesemia, or think you may be dehydrated. Tell your doctor if you have or have ever had a prolonged QT interval, any condition that makes it difficult for you to swallow,trouble keeping your balance, seizures, cataracts, a low number of white blood cells in your blood, high cholesterol, high prolactin levels, high or low blood pressure, a heart attack, a stroke, breast cancer or thyroid, heart or liver disease. If you have ever had to stop taking a medication for mental illness because of severe side effects, be sure to tell your doctor.
  • tell your doctor if you are pregnant, especially if you are in the last few months of your pregnancy, or if you plan to become pregnant or are breast-feeding. If you become pregnant while taking quetiapine, call your doctor. Quetiapine may cause problems in newborns following delivery if it is taken during the last months of pregnancy. You should not breast-feed while taking quetiapine.
  • if you are having surgery, including dental surgery, tell your doctor or dentist that you are taking quetiapine.
  • you should know that quetiapine may make you drowsy. Do not drive a car or operate machinery and take precautions to avoid falls until you know how this medication affects you.
  • you should know that alcohol can add to the drowsiness caused by this medication. Do not drink alcohol while taking quetiapine.
  • you should know that you may experience hyperglycemia (increases in your blood sugar) while you are taking this medication, even if you do not already have diabetes. If you have schizophrenia, you are more likely to develop diabetes than people who do not have schizophrenia, and taking quetiapine or similar medications may increase this risk. Tell your doctor immediately if you have any of the following symptoms while you are taking quetiapine: extreme thirst, frequent urination, extreme hunger, blurred vision, or weakness. It is very important to call your doctor as soon as you have any of these symptoms, because high blood sugar can cause a serious condition called ketoacidosis. Ketoacidosis may become life-threatening if it is not treated at an early stage. Symptoms of ketoacidosis include: dry mouth, nausea and vomiting, shortness of breath, breath that smells fruity, and decreased consciousness.
  • you should know that quetiapine may make it harder for your body to cool down when it gets very hot. While you are taking quetiapine, you should avoid excessive exercise, stay inside as much as possible and dress lightly in hot weather, stay out of the sun, and drink plenty of fluids.
  • you should know that quetiapine may cause dizziness, lightheadedness, and fainting when you get up too quickly from a lying position. This is more common when you first start taking quetiapine and when your dose is increased. To avoid this problem, get out of bed slowly, resting your feet on the floor for a few minutes before standing up.
  • you should know that quetiapine may cause an increase in blood pressure in children and teenagers taking quetiapine. When quetiapine is used in children or teenagers, your doctor will check your blood pressure before starting treatment and regularly while you are taking this medication.
  • you should know that when quetiapine is used to treat schizophrenia or bipolar disorder in children, it should be used as part of a total treatment program which may include counseling and special education. Make sure to follow all of your doctor’s and/or therapist’s instructions.

Recently, after morning rounds seeing patients admitted to his hospital through emergency, Dr. David Juurlink tweeted: “Can the next doctor wanting to prescribe Seroquel for sleep,” he said, “just not?”

Of the roughly 20 patients he saw that morning, four had been prescribed Seroquel, an antipsychotic, for insomnia.

Seroquel and its generics aren’t approved as sleeping pills. Quetiapine, the active ingredient, has been officially approved in Canada for schizophrenia, bipolar disorder and major depression only. Yet drug safety experts are growing increasingly alarmed by the drug’s use as a doctor-prescribed nightcap for insomnia, with a 10-fold increase in quetiapine prescriptions for sleep problems in Canada between 2005 and 2012 alone.

Quetiapine is sedating. Like over-the-counter sleep aids, it makes people drowsy. But it also comes with a multitude of potential side effects, experts say, including an odd sensation of tension and restlessness (akathisia), Parkinson’s-like tremors and movement abnormalities, weight-gain, high blood sugar, new or worsening diabetes and, in rare cases, heart arrhythmia that can cause sudden cardiac death. A recent Health Canada review linked quetiapine and other so-called “atypical” antipsychotics to an increased risk of sleep apnea —breaks in breathing during sleep.

Juurlink, a clinical toxicologist at Sunnybrook Health Sciences Centre in Toronto, said quetiapine could also cause a particularly nasty complication known as neuroleptic malignant syndrome, a rare but potentially life-threatening reaction to antipsychotics or major tranquilizers. “Over the last decade, I have seen several patients who have had quetiapine as part of, or one of the contributing causes to NMS,” said Juurlink, whose frustrated tweet to doctors last week was a repeat of one he has sent before.

Feeling the need to repeat this after rounds this morning …

— David Juurlink (@DavidJuurlink) May 30, 2017

“I’ve certainly seen people who have been diagnosed with Parkinson’s disease that I’m confident were from quetiapine,” he added. “It’s getting to the point now where, when I admit a patient with Parkinson’s, I reflexively look at their other medications to see, ‘are they on quetiapine?’”

According to drug market research firm IMS Brogan, of the 33 million prescriptions for tranquilizers dispensed by Canadian retail drugstores in 2016, one quarter — 8.3 million — were for quetiapine.

Doctors say the drug is being prescribed in low dose formulations to people with no underlying psychiatric conditions, the majority for sleep. University of B.C. researchers found that 58 per cent of B.C. quetiapine prescriptions in 2010 were for the 25mg tablet. The recommended dose range for approved disorders is 150 to 800 mg per day.

“It’s popping up as a patient’s typical medication for insomnia all the time,” says Kamloops emergency physician Dr. Ian Mitchell. “It’s not well supported by any science for use in sleep, it has significant side effects and yet it’s massively prescribed.”

The patients Juurlink saw last week had come through emergency for different reasons, some of them unrelated to Seroquel. “But at least one of them had Parkinson’s disease and this is exactly the kind of drug you don’t want to give to a Parkinson’s patient.”

A 2016 study by McGill University researchers found quetiapine was given to one in eight (13 per cent) of consecutive patients aged 60 and older admitted to Montreal’s Royal Victoria Hospital, with nearly two-thirds of the use for sleep. One in seven who first received the antipsychotic for sleep in the hospital was sent home with at least a one-month prescription.

“Seroquel is not benign,” Dr. David Gardner, a professor of psychiatry and pharmacology at Dalhousie University said in an email. “It may be more dangerous than our standard sleeping pills, but without research we cannot know or quantify its risks.”

It’s not clear how antipsychotics have become such a big thing for sleep. But observers point to aggressive marketing and industry-funded “opinion leaders” who’ve described quetiapine as a “mild, not harmful” drug that seems to help with sleep.

In 2010, pharmaceutical giant AstraZeneca paid US$520 million to resolve allegations it illegally marketed Seroquel in the U.S. for uses never approved by the FDA (Food and Drug Administration), including aggression, dementia and sleeplessness.

The U.S. Department of Justice accused AstraZeneca of “improperly and unduly” influencing the content of and speakers in, company-sponsored continued medical education programs, and of paying doctors to give promotional speeches and pose as authors on ghostwritten articles.

The company denied the allegations but agreed to the payment.

Some users swear by it. “Seroquel helps me for sleep when nothing else will,” according to one online reviewer. “The only bad thing is 30 (minutes) to one hour after taking it, I’m starving!!” Others describe feeling spacey and foggy the next morning.

Juurlink said quetiapine might shorten sleep latency — the time it takes to fully fall asleep — by a few minutes. It can also make people less aware of their “nocturnal awakenings” than they might otherwise have been. It’s a potent antihistamine, like diphenhydramine, the active ingredient in Benadryl and other “nighttime” cold remedies.

“But what’s really driving this is a societal expectation that we should all get eight hours of sleep a night, a pill is a way to go about it, and the willingness of some providers to accede to requests for sleeping pills,” Juurlink said.

While quietiapine has proven safe and effective for approved conditions, and most of the side effects have been reported during high dose treatment, side effects such as tardive dyskinesia — abnormal movements of the face and jaw — have been reported with low dose regimens as well, according to the UBC Therapeutics Initiative.

Abuse of quetiapine is also a growing problem, with people inhaling or injecting crushed or dissolved tablets. Street names for quetiapine include “Suzy Q” and “baby heroin.”

Mitchell says it’s hard to explain the “inherent hypocrisy” of the massive prescribing of an antipsychotic for insomnia, while medical leaders are warning doctors to be wary of prescribing marijuana for sleep.

“I’m not asking people to smoke a joint in a nursing home for sleep, that’s not what this is about,” he said. “But there may be some alternatives to some of the damaging medications that are out there, or ways to replace them with cannabis.”

In Australia, in a bid to curb escalating use of quetiapine for unapproved conditions, the number of government-subsidized repeat prescriptions for low dose Seroquel has been reduced from five, to zero.

Dr. Dee Mangin, a former New Zealand family physician and now professor of family medicine at McMaster University, recommends basic sleep hygiene, “obvious things like not drinking caffeine or exercising too close to bed, making the sleeping environment restful and relaxing, not looking at screens of any sort in that time just before bed.” People should also look at what’s causing the sleeplessness and ways to manage stress, “rather than focusing on the insomnia itself.”

National Post

• Email: [email protected] | Twitter: sharon_kirkey ‏

Generic Name: quetiapine (kwe TYE a peen)
Brand Names: SEROquel, SEROquel XR

Medically reviewed by Sophia Entringer, PharmD Last updated on Nov 4, 2019.

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What is Seroquel?

Seroquel (quetiapine) is an antipsychotic medicine. It works by changing the actions of chemicals in the brain.

Seroquel is used to treat schizophrenia in adults and children who are at least 13 years old.

Seroquel is used to treat bipolar disorder (manic depression) in adults and children who are at least 10 years old.

Seroquel is also used together with antidepressant medications to treat major depressive disorder in adults.

Seroquel may also be used for purposes not listed in this medication guide.

Important information

Never take Seroquel in larger amounts, or for longer than recommended by your doctor. High doses or long-term use can cause a serious movement disorder that may not be reversible. Symptoms of this disorder include tremors or other uncontrollable muscle movements.

Stop using Seroquel and call your doctor at once if you have the following symptoms: very stiff (rigid) muscles, high fever, sweating, confusion, fast or uneven heartbeats, tremors, uncontrolled muscle movements, feeling light-headed, blurred vision, eye pain, increased thirst and urination, excessive hunger, fruity breath odor, weakness, nausea and vomiting.

Some young people have thoughts about suicide when first taking Seroquel. Stay alert to changes in your mood or symptoms. Report any new or worsening symptoms to your doctor.

Seroquel is not FDA approved for use in psychotic conditions related to dementia. Quetiapine may increase the risk of death in older adults with dementia-related conditions.

Before taking this medicine

You should not use Seroquel if you are allergic to quetiapine.

Seroquel is not FDA approved for use in psychotic conditions related to dementia. Quetiapine may increase the risk of death in older adults with dementia-related conditions.

To make sure Seroquel is safe for you, tell your doctor if you have:

  • liver or kidney disease;

  • heart disease, heart rhythm problems, a history of heart attack or stroke;

  • high or low blood pressure;

  • a history of low white blood cell (WBC) counts;

  • abnormal thyroid tests or prolactin levels;

  • seizures or epilepsy;

  • cataracts;

  • high cholesterol or triglycerides;

  • a personal or family history of diabetes; or

  • trouble swallowing.

Some young people have thoughts about suicide when first taking Seroquel. Your doctor will need to check your progress at regular visits. Your family or other caregivers should also be alert to changes in your mood or symptoms.

Taking antipsychotic medication during the last 3 months of pregnancy may cause problems in the newborn, such as withdrawal symptoms, breathing problems, feeding problems, fussiness, tremors, and limp or stiff muscles. However, you may have withdrawal symptoms or other problems if you stop taking your medicine during pregnancy. If you become pregnant while taking Seroquel, do not stop taking it without your doctor’s advice.

This medicine may temporarily affect fertility (your ability to have children) in women.

Seroquel can pass into breast milk and may harm a nursing baby. You should not breastfeed while you are using Seroquel unless directed by a doctor.

Do not give Seroquel to a child without a doctor’s advice. Extended-release Seroquel XR is for use only in adults and should not be given to anyone younger than 18 years old.

How should I take Seroquel?

Never take Seroquel in larger amounts, or for longer than recommended by your doctor. Follow all directions on your prescription label. High doses or long-term use of quetiapine can cause a serious movement disorder that may not be reversible. Symptoms of this disorder include tremors or other uncontrollable muscle movements.

Take this medicine with a full glass of water. You may take immediate-release Seroquel with or without food. It is suggested that Seroquel XR be administered without food or with a light meal (< 300 calories), preferably in the evening.

Do not crush, chew, or break an extended-release tablet. Swallow it whole.

Seroquel may cause you to have high blood sugar (hyperglycemia). If you are diabetic, check your blood sugar levels on a regular basis while you are taking Seroquel.

You should not stop using Seroquel suddenly. Stopping suddenly may make your condition worse.

Blood pressure may need to be checked often in a child or teenager taking Seroquel.

Quetiapine can cause you to have a false positive drug screening test. If you provide a urine sample for drug screening, tell the laboratory staff that you are taking Seroquel.

Store at room temperature away from moisture and heat.

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222. An overdose of quetiapine can be fatal.

What should I avoid while taking Seroquel?

Avoid drinking alcohol. Dangerous side effects could occur.

Seroquel may impair your thinking or reactions. Avoid driving or operating machinery until you know how this medicine will affect you.

Avoid getting up too fast from a sitting or lying position, or you may feel dizzy. Dizziness or severe drowsiness can cause falls, fractures, or other injuries.

Avoid becoming overheated or dehydrated during exercise and in hot weather. You may be more prone to heat stroke.

Seroquel side effects

Get emergency medical help if you have signs of an allergic reaction to Seroquel: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Report any new or worsening symptoms to your doctor, such as: mood or behavior changes, anxiety, panic attacks, trouble sleeping, or if you feel impulsive, irritable, agitated, hostile, aggressive, restless, hyperactive (mentally or physically), more depressed, or have thoughts about suicide or hurting yourself.

Call your doctor at once if you have:

  • uncontrolled muscle movements in your face (chewing, lip smacking, frowning, tongue movement, blinking or eye movement);

  • mask-like appearance of the face, trouble swallowing, problems with speech;

  • a light-headed feeling, like you might pass out;

  • blurred vision, tunnel vision, eye pain, or seeing halos around lights;

  • severe nervous system reaction – very stiff (rigid) muscles, high fever, sweating, confusion, fast or uneven heartbeats, tremors, fainting;

  • high blood sugar – increased thirst, increased urination, hunger, dry mouth, fruity breath odor, drowsiness, dry skin, blurred vision, weight loss; or

  • low blood cell counts – sudden weakness or ill feeling, fever, chills, cold or flu symptoms, cough, sore throat, red or swollen gums, painful mouth sores, skin sores, trouble breathing.

Common Seroquel side effects may include:

  • trouble with movement;

  • dizziness, weakness;

  • increased appetite, weight gain;

  • sore throat;

  • dry mouth; or

  • nausea, vomiting, stomach pain, constipation.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect Seroquel?

Seroquel can cause a serious heart problem if you use certain medicines at the same time, including certain antibiotics, antidepressants, heart rhythm medicine, antipsychotic medicines, and medicines to treat cancer, malaria, HIV or AIDS. Tell your doctor about all medicines you use, and those you start or stop using during your treatment with Seroquel.

Taking Seroquel with other drugs that make you sleepy or slow your breathing can cause dangerous or life-threatening side effects. Ask your doctor before taking a sleeping pill, narcotic pain medicine, prescription cough medicine, a muscle relaxer, or medicine for anxiety, depression, or seizures.

Many drugs can interact with quetiapine. Not all possible interactions are listed here. Tell your doctor about all your current medicines and any you start or stop using, especially:

  • antibiotic or antifungal medicines;

  • antiviral medicine to treat hepatitis or HIV/AIDS;

  • heart or blood pressure medicines;

  • medicine to treat mental illness;

  • St. John’s wort;

  • seizure medicine; or

  • medicines used to treat tuberculosis.

This list is not complete and many other drugs can interact with quetiapine. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Give a list of all your medicines to any healthcare provider who treats you.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Seroquel only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Copyright 1996-2020 Cerner Multum, Inc. Version: 16.01.

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Seroquel Side Effects (Generic Name: Quetiapine)

Seroquel (quetiapine)

Seroquel is the brand name for an atypical, second generation antipsychotic drug called quetiapine.1 As a prescription medication used to treat serious mental illnesses like bipolar disorder and schizophrenia, qutiapine is a valuable pharmaceutical tool used by practitioners to mitigate certain mental health symptoms and improve the wellbeing of their patients.2″

Is Seroquel Dangerous?

Despite the many benefits of Seroquel (quetiapine), the drug carries a risk of side effects and some danger of lasting health consequences. Like many other psychoactive prescription medications, there is emerging evidence to suggest Seroquel is sometimes misused.1 Although the drug’s use is generally safe, it is valuable to know and understand the possible repercussions of use in order to keep yourself and your loved ones safe

Call 972-895-9190 to start life-changing care at Greenhouse Treatment Center. It’s free and confidential.

Common, Short-Term Side Effects of Seroquel

Unfortunately, Seroquel has many unwanted side effects that can present even in people who take the substance as directed. Some may resolve over a few days while others have the potential to persist throughout the duration of treatment.

Common, short-term side effects of Seroquel may include:3

  • Trouble thinking.
  • Problems speaking.
  • Unusual dreams.
  • Irritability and mood swings.
  • Weight gain.
  • Indigestion.
  • Constipation.
  • Dry mouth.
  • Dizziness.
  • Headaches.
  • Muscle weakness.

Seroquel may also be associated with certain hormonal changes, resulting in side effects such as:3

  • Increased breast tissue in men (gynecomastia).
  • Irregular or dropped menstrual periods in women (dysmenorrhea or amenorrhea).
  • Lowered interest in sex or ability to perform sexually.

Rare / Serious Side Effects of Seroquel

Seroquel use is sometimes associated with more serious side effects, including:3

  • Fainting.
  • Confusion.
  • Unexpected or uncontrollable movements in your arms, legs, face, tongue, or lips.
  • Heart rate changes.
  • Vision changes.
  • Trouble breathing.

As with other drugs, Seroquel may be more likely to have adverse outcomes in people who abuse the substance. Often in these scenarios, dosing is not able to be supervised or adjusted, nor is a medical professional able to monitor or respond to an individual’s ongoing health status adequately.

Seroquel Abuse

Though Seroquel has known pharmacotherapeutic uses, is not a controlled substance, and is not generally considered to have a high potential for abuse or addiction, there have been reports of the medication being misused or abused. It is sometimes abused in combination with cocaine.2 The combination of Seroquel and cocaine is sometimes called a “Q-ball.”2

Other potential slang or street terms used to refer to Seroquel as a drug of abuse include:1

  • Baby heroin
  • Quell.
  • Susie-Q.

While rates of Seroquel abuse are low on the whole, there have been reports of people abusing it various ways—via oral route, by crushing and snorting it, and by injecting it.1

There is debate about why Seroquel, more than other antipsychotics, tends to be abused; however, some hypothesize that the sedating effects play a part.1

A study found that Seroquel was the only atypical antipsychotic drug to be somewhat desirable on the street. One dose of Seroquel has a reported street value of between $3 and $8 for a 25 mg pill.1

Seroquel abuse is likely to be more prevalent in prison and inpatient psychiatric populations. In these settings, people have been reported to feign psychotic symptoms like hallucinations or delusions to obtain Seroquel prescriptions from staff.2

Chronic, Long-Term Effects of Seroquel Abuse

Over time, especially if abused, Seroquel can lead to the development of several adverse, and potentially long-lasting side effects. In some instances, these effects are reversible when use of the drug ends, but in other situations, the changes can be permanent.

Weight Gain

One of the most commonly reported side effects is weight gain.4 Over time, excess weight can harm the heart, lungs, stomach, liver, pancreas, and other organs. While many people gain weight while taking Seroquel as prescribed, the result isn’t inevitable. Some are able to remain within a healthy weight by following their doctors’ orders regarding a healthy balance of diet and exercise.


Along with the added weight, Seroquel carries a risk of other metabolic problems like increased blood sugar.4 There is a link between using Seroquel and diabetes diagnoses. The high blood sugar associated with Seroquel can, in some cases, be extreme and lead to a precipitous drop in blood pH levels (ketoacidosis), coma, or death.

Signs of persistent hyperglycemia (high blood sugar) may include:4

  • Feeling very thirsty.
  • Frequent urination.
  • Increased hunger.
  • Feeling weak or tired.
  • Intense nausea or feeling sick to your stomach.
  • A fruity smell to your breath.
  • Periods of confusion or disorientation.

High Cholesterol

High cholesterol can also be harmful, increasing the risk of strokes or heart attacks. Having high cholesterol and blood pressure is often associated with being overweight or having an unhealthy life style. Abusing Seroquel puts one at risk of developing these conditions related to weight gain.

long-term physical effects associated with Seroquel include:

Tardive dyskinesia:

This condition affects a person’s nervous system and is characterized by numerous involuntary movements. A person with tardive dyskinesia may lose the ability to control their facial expressions and experience impaired use of their tongue and mouth. Worse, the condition may be irreversible.

Blood pressure changes:

Seroquel use is known to result in some alterations in the blood pressure of those who use it. Interestingly, children and adolescents using the drug will generally experience higher blood pressure (hypertension) while adults will likely experience lower blood pressure (hypotension). Both conditions are potentially problematic and require further observation to assess any risks to the patient (such as increased risk of falls related to hypotensive episodes; see below).

Risk of falls:

People using Seroquel are in greater danger of falling and sustaining injuries from the fall. This danger is due to a combination of sleepiness, poor coordination, sensory instability, and low blood pressure.

Low white blood cell count:

Seroquel may reduce the number of white blood cells (WBC) in the body, especially among those with a history of low WBCs. Having a pathologically low white blood cell count (leukopenia) can be dangerous because these cells normally fight infection; having a low WBC count could expose the user to an increased risk of infection.


Using Seroquel increases the chances of developing cataracts, which can blur and minimize vision.

Thyroid problems:

Taking Seroquel may decrease the thyroid hormone levels. This may worsen as the dose increases.

Swallowing issues:

Seroquel makes it more difficult to swallow, which may lead to aspiration pneumonia from food being inhaled into the lungs rather than being swallowed into the stomach.

Increased body temperature: Using Seroquel disrupts the body’s natural ability to manage and regulate heat and core temperature. Without care, people who exercise rigorously or are exposed to hot climates can become dehydrated more easily.


Though the risk is slight, it is still worthwhile to mention the increase in seizures seen with Seroquel use among the general population. People with a history of seizures or other conditions that trigger seizures may be at an increased risk.

Cardiac issues:

Seroquel, especially when combined with other medications, can result in heart rate abnormalities, which may result in cardiac emergencies.

Is Seroquel Safe for the Elderly

Certain populations may be at even greater risk of Seroquel-associated adverse events. For instance, when used in elderly people with dementia-related psychosis, Seroquel increases the risk of stroke and death from heart failure or infections like pneumonia.4 Due to these serious hazards, this population should only use Seroquel when no other options exist.

Seroquel Overdose

While it is possible to overdose on quetiapine, the likelihood is quite low. People have consumed 30 grams of the drug and survived.4 This amount is very large considering the maximum dose of Seroquel is 800 mg daily for most people with bipolar disorder and schizophrenia and only 300 mg daily for people as an adjunctive treatment for depression.4 Despite this relatively large index of safety, taking larger than recommended doses of the medication is never advisable.

A Seroquel overdose may result in unwanted effects like:4

  • Marked sedation/drowsiness.
  • Cardiac abnormalities (e.g., QT elevation).
  • Rapid heart rate (tachycardia).
  • Low blood pressure.

Although very rare, overdose could result in coma and death in some individuals.4

There is no Seroquel overdose antidote, so anyone who may have overdosed should contact emergency services or present to the nearest emergency room immediately. Once there, the staff will focus on airway support, ventilation assistance (if needed), and clearing the GI tract of any remaining Seroquel through gastric lavage, administration of activated charcoal, and laxatives.4

Psychological Effects of Seroquel

Depression, bipolar disorder, and schizophrenia are serious mental health conditions which can severely decrease a person’s quality of life. Overall, Seroquel has the ability to greatly improve the mental health of children, adolescents, and adults with various psychiatric issues.

Sadly, Seroquel can also negatively influence someone’s mental health and well-being just as it can impair their physical health. The drug has the ability to impair judgment, reduce decision-making skills, and alertness.4 For these reasons, someone using Seroquel should avoid situations where they could endanger themselves or others like when driving a car or operating machinery.

Suicidal thoughts and behaviors are another significant psychological effect of Seroquel to be aware of. People with a major depressive disorder who begin using Seroquel may report an increase in depression, which may result in suicide.4 This pattern has occurred in adults who use Seroquel, but the trend seems more prevalent in people 24 years of age or younger than in older adults.4

Suicidal ideation has occurred in some children, teens, and young adults who use Seroquel. Young people who suffer from depression or another mental illness and who abuse Seroquel recreationally may be hesitant to disclose their symptoms to a doctor for fear of getting in trouble and may not get the proper treatment.

Does Seroquel Cause Withdrawal Symptoms?

Many prescription and illicit drugs are associated with certain withdrawal symptoms when use is stopped or drastically reduced after the body has become accustomed to the substance’s presence in the body.

Seroquel withdrawal may include symptoms such as:4

  • Trouble falling asleep or staying asleep.
  • Dizziness.
  • Headache.
  • Nausea and vomiting.
  • Diarrhea
  • Irritability

These Seroquel withdrawal effects are uncomfortable, but they are a normal and expected part of the process. The symptoms will usually alleviate within a week of last use.4 Slowly lowering the dose under the care of a doctor can minimize any withdrawal discomfort.4

Using Seroquel as directed can drastically improve mental health and wellbeing, but it can also trigger some significantly negative side effects and long-term consequences. Though abusing Seroquel may be rare, it can also increase the harm in a number of ways. Long-term abuse may increase the risk of serious, chronic health issues.

If you or a loved one are abusing Seroquel or experiencing unwanted effects from the substance, it is important to let a professional know. Getting help to switch to another medication or to overcome abuse of this psychiatric medication can dramatically improve your quality of life.

Disclaimer: “This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.


What is Seroquel?

Seroquel is a medication known as an atypical antipsychotic that is used to treat symptoms of schizophrenia. The medication is also sometimes used to treat symptoms of bipolar disorder.

When did the U.S. Food and Drug Administration (FDA) approve the medication?

Seroquel was first approved by the FDA in 1997.

Is there a generic version of Seroquel?

Yes, quetiapine is the generic version of Seroquel and is available in the United States.

Are there any major differences between Seroquel and other antipsychotics used to treat Seroquel?

Seroquel belongs to the class of medications known as atypical antipsychotics or second generation psychotics. It is available in regular and extended-release forms. The drug is also used to treat symptoms of bipolar disorder. It can cause an increase in suicidal thoughts and behaviors among children, teens, and young adults. Talk to your doctor about what might work best for you and the costs and benefits of taking the medication. Some people may need to try several different antipsychotics before they find the most effective with the fewest side effects.

Can children take Seroquel?

Seroquel has been approved to treat schizophrenia in children ages 13 and older. However, teens taking atypical antipsychotics can be at higher risk for side effects such as weight gain and suicidal thoughts and behaviors. Talk to your child’s doctor about the risks of using the medication.

Are there potential interaction issues for people taking Seroquel and any other drugs?

There are hundreds of other drugs known to interact with Seroquel in major, moderate, or mild ways, so let your doctor know what other medications you are taking before you begin taking the medication. Some of these include antidepressants, antifungals, antihistamines, barbiturates, carbamazepine, chlorpromazine; divalproex, dopamine agonists, erythromycin, gatifloxacin, levodopa, levomethadyl acetate, HIV medications, methadone, moxifloxacin, pentamidine, phenytoin, rifampin, sedative, oral steroids, methylprednisolone, and prednisone, sleeping pills, thioridazine, tranquilizers, and ziprasidone. Also talk to your doctor if you are taking medication for irregular heartbeat, anxiety, high blood pressure, irritable bowel disease, motion sickness, Parkinson’s disease, ulcer, urinary problems, or any other mental health issues.

Are there any other medical conditions that would make someone ineligible for Seroquel therapy?

Talk to your doctor about other medical conditions before you take Seroquel, such as a prolonged QT interval, diabetes, dementia, seizures, cataracts, low white blood cell count, high cholesterol, high or low blood pressure, a history of heart attack or stroke, breast cancer, thyroid cancer, heart disease, or liver disease. Also talk to your doctor if you have a history of substance abuse or any other mental health issues, including a history of suicidal thoughts.

What is the typical starting dose that would be prescribed to someone taking Seroquel?

The FDA recommends a starting dosage of 25mg twice a day for the treatment of schizophrenia. The safety of doses above 800 mg per day has not been established. Dosage may differ for the extended-release version of the medication and for the treatment of bipolar disorder.

What do I do if I miss a dose?

Take the dose of Seroquel when you remember, but skip the missed dose if it it’s almost time for your next dose. You should never take extra doses of the medication to make up for missed doses.

Can Seroquel cause side effects?

Common side effects of Seroquel can include:

  • Dizziness
  • Drowsiness
  • Dry mouth
  • Vomiting
  • Constipation
  • Weight gain
  • Headaches
  • Stuffy nose
  • Joint, back, or neck pain
  • Irritability
  • Difficulty speaking
  • Difficulty concentrating
  • Indigestion
  • Strange dreams
  • Stomach pain
  • Weakness
  • Numbness in arms or legs
  • Missed menstrual periods
  • Decreased sex drive.

Doctors recommend that you not drink alcohol while on the medication. It also is recommended that you wait to drive or operate machinery until you know how the medication affects you. Report major side effects to your doctor immediately, which can include fainting, vision changes, fever, seizures, confusion, painful and long-lasting erection, sweating, uncontrollable movements, muscle pain or stiffness, unusual bleeding or bruising, signs of infection, rash, fast or irregular heartbeat, tightening of throat, and difficulty breathing or swallowing. You can also report side effects to the FDA at 1-800-FDA-1088 or online.

What are the potential long-term effects of taking Seroquel?

Your doctor should monitor for progression of potential long-term side effect of Seroquel, which can include cataracts, weight gain, high blood sugar, high cholesterol, and tardive dyskinesia.

Is it safe for a woman who is pregnant, about to become pregnant, or nursing to take Seroquel?

There have been no controlled human pregnancy studies on the effects of Seroquel. The drug can be transferred via human breast milk and potentially harm a baby. Therefore, talk to your doctor if you are pregnant, planning to become pregnant, or are nursing before you take Seroquel.

Can symptoms occur if Seroquel is discontinued?

It’s important not to discontinue use of the drug if you feel better. Withdrawal symptoms may include nausea, vomiting, diarrhea, headaches, dizziness, irritability, and the return of symptoms of schizophrenia. Maintain contact with your doctor and seek medical attention if necessary when discontinuing the drug, and talk to your doctor about how to mitigate potential withdrawal symptoms.

What should I do if I overdose on Seroquel?

Seek immediate help or call the Poison Help Line at 1-800-222-1222 if you overdose, as it can be fatal. Symptoms may include drowsiness, fast heartbeat, fainting, and dizziness.

Is Seroquel habit-forming?
Seroquel has no habit-forming potential, but it is not recommended that you discontinue use of the drug before talking with your doctor, as withdrawal symptoms can occur.

How much does Seroquel cost?

According to, 30 tablets of 25mg Seroquel cost approximately $130. 30 tablets of 25mg generic quetiapine cost approximately $20.

Are there any disadvantages to Seroquel?

The biggest disadvantages of Seroquel are the potential long-term side effects, which can include tardive dyskinesia, increased blood sugar, cataracts, and weight gain. For teens and young adults, the medication may also cause an increase in suicidal thoughts and behaviors.

DISCLAIMER: The information contained herein should NOT be used as a substitute for the advice of an appropriately qualified and licensed physician or other health care provider. This article mentions drugs that were FDA-approved and available at the time of publication and may not include all possible drug interactions or all FDA warnings or alerts. The author of this page explicitly does not endorse this drug or any specific treatment method. If you have health questions or concerns about interactions, please check with your physician or go to the FDA site for a comprehensive list of warnings.

Article Sources Last Updated: Nov 25, 2018

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