Hydroxyzine 50 mg high


Vistaril is the brand name for hydroxyzine pamoate, a prescription drug used to treat:

  • Anxiety and tension
  • Nausea and vomiting
  • Severe itching (pruritus) from allergic conditions, such as chronic hives (urticaria) and contact dermatitis

It’s also used as a sedative for general anesthesia.

Vistaril is a central nervous system depressant and antihistamine, which works by reducing the activity of the natural chemical histamine.

In the body, histamines are involved in local immune and inflammatory responses, producing symptoms such as sneezing, running nose, and itchy hives. Histamines also play a vital role as a neurotransmitter in the central nervous system.

Doctors may also prescribe Vistaril off-label to treat insomnia and the symptoms of opioid withdrawal.

Manufactured by Pfizer, Vistaril was first approved by the Food and Drug Administration (FDA) in 1968. Roerig, a division of Pfizer, also manufactured a similar drug called Atarax (hydroxyzine hydrochloride), which was FDA-approved in 1956 and discontinued in the United States in 2009.

In 2014, the European Medicines Agency (EMA) — the European Union’s FDA — announced that it would begin reviewing the benefits and risks of hydroxyzine-containing medications, including Vistaril, due to concerns about the drugs’ potential negative effects to the heart, including causing arrhythmias (irregular heartbeat).

The results of the EMA review could alter the approval of Vistaril throughout Europe.

Vistaril Warnings

You should not use Vistaril if you are allergic or sensitive to hydroxyzine.

As with other antihistamines, you should not drive a car or operate dangerous machinery while taking Vistaril, as the drug can make you drowsy. Taking Vistaril with other sedating medicines or alcohol could increase the feeling of drowsiness.

Vistaril can increase the effectiveness of drugs that reduce the activity of the central nervous system, including narcotics, non-narcotic analgesics (pain relievers), and barbiturates (sedatives). Because of this, the dosage of these drugs should be reduced while taking Vistaril.

Before taking Vistaril, your doctor needs to know if you have heart or liver disease, trouble urinating due to an enlarged prostate gland, glaucoma, ulcers, high blood pressure, seizures, or thyroid problems.

Pregnancy and Vistaril

Vistaril should not be used during early pregnancy. In animal studies, hydroxyzine caused fetal abnormalities in rats and mice (though no adequate studies have been conducted in pregnant women).

You should not take Vistaril if you are breastfeeding because it’s unknown if the drug is excreted in breast milk.

The ‘Hydroxyzine High’ and Abuse

Intentionally overdosing on Vistaril can cause hypersedation; the drug can also cause hallucinations, even under normal doses. Additionally, hydroxyzine can enhance the effects of opioid drugs, including morphine, oxycodone, and heroin.

Vistaril is non-habit forming, but people may seek out the drug specifically to abuse it and get a feeling of being “high” (though the drug doesn’t induce euphoria by itself).

Hydroxyzine for Dogs and Cats

Hydroxyzine is sometimes given to cats and dogs to treat allergic conditions, such as atopic dermatitis (chronic skin disorder causing scaly and itchy rashes), as well as allergic reactions from snake and insect bites.

It’s also sometimes used to reduce pets’ anxiety or to sedate them.


Generic Name: hydroxyzine (hye DROX ee zeen)
Brand Names: ANX, Vistaril, Atarax, Vistaril IM, Hyzine, Vistaject-50, Rezine

Medically reviewed by Sophia Entringer, PharmD Last updated on Dec 18, 2018.

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What is hydroxyzine?

Hydroxyzine is an antihistamine that reduces the effects of natural chemical histamine in the body. Histamine can produce symptoms of itching, or hives on the skin. Hydroxyzine may be used to treat allergic skin reactions such as hives or contact dermatitis.

Since hydroxyzine also reduces activity in the central nervous system, it can be used as a sedative to treat anxiety and tension. It is also used together with other medications given during and after general anesthesia.

Hydroxyzine is also used to treat allergic skin reactions such as hives or contact dermatitis.

Important information

Hydroxyzine may cause birth defects. Talk to you doctor before using hydroxyzine if pregnant or breastfeeding.

Hydroxyzine can cause a serious heart problem, especially if you use certain medicines at the same time. Tell your doctor about all your current medicines and any you start or stop using.

This medication may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.

Stop using this medicine and call your doctor at once if you have a serious side effect such as tremors, confusion, seizures, or restless muscle movements in your eyes, tongue, jaw, or neck.

Drinking alcohol can increase certain side effects of hydroxyzine.

Before taking this medicine

You should not use hydroxyzine if you are allergic to it, or if:

  • you have long QT syndrome;

  • you are allergic to cetirizine (Zyrtec) or levocetirizine (Xyzal); or

Hydroxyzine could harm the unborn baby or cause birth defects. Talk to you doctor before using hydroxyzine if pregnant.

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

  • blockage in your digestive tract (stomach or intestines);

  • bladder obstruction or other urination problems;

  • glaucoma;

  • heart disease, slow heartbeats;

  • personal or family history of long QT syndrome;

  • an electrolyte imbalance (such as high or low levels of potassium in your blood);

  • if you have recently had a heart attack.

It is not known whether hydroxyzine passes into breast milk or if it could harm a nursing baby. Talk to your doctor before breastfeeding while using this medicine.

Do not give this medicine to a child without medical advice.

How should I take hydroxyzine?

Take hydroxyzine exactly as prescribed by your doctor. Follow all directions on your prescription label. Your doctor may occasionally change your dose. Do not use this medicine in larger or smaller amounts or for longer than recommended.

Shake the oral suspension (liquid) well just before you measure a dose. Measure liquid medicine with the dosing syringe provided, or with a special dose-measuring spoon or medicine cup. If you do not have a dose-measuring device, ask your pharmacist for one.

Hydroxyzine is for short-term use only.

You should not take this medicine for longer than 4 months. Call your doctor if your anxiety symptoms do not improve, or if they get worse.

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.

Overdose symptoms may include severe drowsiness, nausea, vomiting, uncontrolled muscle movements, or seizure (convulsions).

What should I avoid while taking hydroxyzine?

This medicine may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.

Drinking alcohol with this medicine can cause side effects.

Hydroxyzine side effects

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

In rare cases, hydroxyzine may cause a severe skin reaction. Stop taking this medicine and call your doctor right away if you have sudden skin redness or a rash that spreads and causes white or yellow pustules, blistering, or peeling.

Stop using hydroxyzine and call your doctor at once if you have:

  • fast or pounding heartbeats;

  • headache with chest pain;

  • severe dizziness, fainting; or

  • a seizure (convulsions).

Side effects such as drowsiness and confusion may be more likely in older adults.

Common hydroxyzine side effects may include:

  • drowsiness;

  • headache;

  • dry mouth; or

  • skin rash.

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 hydroxyzine?

Taking this medicine with other drugs that make you sleepy can worsen this effect. Ask your doctor before taking hydroxyzine with a sleeping pill, narcotic pain medicine, muscle relaxer, or medicine for anxiety, depression, or seizures.

Hydroxyzine can cause a serious heart problem, especially if you use certain medicines at the same time, including 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 this medicine.

Other drugs may interact with hydroxyzine, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed here. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.

Further information

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

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

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Other brands: Vistaril, Atarax, Hyzine

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Vistaril vs Xanax: Main Differences and Similarities

Vistaril (hydroxyzine) and Xanax (alprazolam) are two medications used to treat anxiety. Vistaril is an antihistamine with sedative properties while Xanax is a benzodiazepine. Although they work in different ways, both drugs have similar side effects such as drowsiness. Their similarities and differences will be explained in depth below.

Vistaril, known by its generic name, hydroxyzine, is an antihistamine medication with sedative, anxiolytic, and antiemetic effects. While its exact mechanism of action is not entirely known, it is approved to treat anxiety and itching (pruritus). It can also be used as a sedative for surgery before and after general anesthesia.

Vistaril is available as a 25 mg or 50 mg oral capsule. An oral suspension can also be taken. Dosing may be up to four times daily for anxiety although it depends on your doctor’s instruction. While some people may use Vistaril on a long-term basis, long-term use of Vistaril for more than four months has not been evaluated yet by clinical studies.


Xanax is the brand name for alprazolam. It is grouped in a class of medications known as benzodiazepines that work on GABA receptors in the brain. It is approved to treat anxiety and panic disorder.

Xanax is available as an oral tablet with varying strengths of 0.25 mg, 0.5 mg, 1 mg, and 2 mg. Other forms of Xanax include an extended-release tablet, orally disintegrating tablet, and oral solution. For anxiety, it is can be dosed three times per day depending on a doctor’s prescription. Like Vistaril, it is not generally recommended for long-term use especially in the elderly population.

Vistaril vs Xanax Side by Side Comparison

Vistaril and Xanax are two anxiolytic drugs with many similarities and differences. Their drug features can be found in the table below for a closer comparison.

Vistaril Xanax
Prescribed For
  • Anxiety
  • Pruritus
  • Sedation
  • Generalized Anxiety Disorder (GAD)
  • Panic Disorder
Drug Classification
  • Antihistamine
  • Benzodiazepine
  • Pfizer
  • Pfizer
Common Side Effects
  • Drowsiness
  • Dry mouth
  • Confusion
  • Drowsiness
  • Lightheadedness
  • Constipation
  • Restlessness
  • Extreme fatigue
  • Slow heartbeat
  • Trouble breathing
  • Changes in appetite or weight
Is there a generic?
  • Yes, Hydroxyzine pamoate
  • Yes, Alprazolam
Is it covered by insurance?
  • Varies according to your provider
  • Varies according to your provider
Dosage Forms
  • Oral capsule
  • Oral suspension
  • Oral tablet
  • Oral concentrate
  • Oral tablet, extended release
  • Oral tablet, orally disintegrating
Average Cash Price
  • $265 per 100 capsules
  • $42.89 per 90 tablets
SingleCare Discount Price
  • Vistaril Price
  • Xanax Price
Drug Interactions
  • Donepezil
  • Benztropine
  • Clozapine
  • Chlorpromazine
  • Perphenazine
  • Venlafaxine
  • Dronedarone
  • Fluconazole
  • Tacrolimus
  • Haloperidol
  • Phenobarbital
  • Acetaminophen
  • Fentanyl
  • Oxycodone
  • Pimozide
  • Sertraline
  • Tramadol
  • Zolpidem
  • Ketoconazole
  • Itraconazole
  • Clarithromycin
  • Cimetidine
  • Cyclosporine
  • Desipramine
  • Diltiazem
  • Ergotamine
  • Erythromycin
  • Fluconazole
  • Fluoxetine
  • Fluvoxamine
  • Imipramine
  • Nefazodone
  • Nicardipine
  • Nifedipine
  • Sertraline
  • Theophylline
  • Birth control pills
  • Seizure medications
Can I use while planning pregnancy, pregnant, or breastfeeding?
  • Vistaril is in Pregnancy Category C. Consult a doctor regarding steps to take if planning pregnancy or breastfeeding.
  • Xanax is in Pregnancy Category D. Therefore, it should not be taken during pregnancy. Consult a doctor regarding steps to take while planning pregnancy. Xanax should not be taken while breastfeeding.


Vistaril (hydroxyzine) and Xanax (alprazolam) are prescription medications used for anxiety. They work in different ways which make them each unique for different cases. Vistaril can also be used for itching as well as sedation while Xanax primarily treats anxiety and panic disorder.

For anxiety, both medication may need to be taken up to a few times a day. They both also come in oral pill and liquid forms for easier dosing. However, both medications are not usually recommended for long-term use.

Vistaril and Xanax need to be used with caution in the elderly due to increased drowsiness and dizziness. These drugs should also be monitored in those with liver impairment due to the increased risk of other side effects. Because Vistaril is an anticholinergic drug, it can cause drying effects such as dry mouth.

Both medications should be used under the guidance and supervision of a healthcare provider. Xanax has a higher potential of abuse and dependence due to its more severe DEA schedule. It is important to review these medications and other options with a doctor to determine the best option for you.

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Hydroxyzine (pronounced /haɪˈdrɒksɨziːn/) is a first-generation antihistamine, of the piperazine class that is an H1 receptor antagonist. It was synthesised in the early 1950s and the medicinal formulation of this drug was announced in the 04 August 1956 issue of Chemistry Week. It is used primarily as an antihistamine for the treatment of itches and irritations, an antiemetic for the reduction of nausea, as a weak analgesic by itself and as an opioid potentiator, and as an anxiolytic for the treatment of anxiety.

Its most common formulation is 25 mg small white, capsule-shaped and scored tablets of the hydrochloride salt made by UCB in the Netherlands. In the United States, a nearly-spherical dark green tablet is the most-commonly encountered version of it, with 25 and 100 mg capsules being available as well as a series of colour-coded round tablets from Mallinkrodt (25 mg white, 50 mg orange, 100 mg blue). Hydroxyzine preparations usually require a doctor’s prescription as do other potent antihistamines in many countries whereas some countries allow hydroxyzine and all or most other antihistamines to be sold over the counter.

Even though it is an effective sedative, hypnotic, and tranquilliser, it shares almost none of the abuse, dependence, addiction, and toxicity potential of other drugs used for the same range of therapeutic reasons. The drug is available in two formulations, the pamoate and the dihydrochloride or hydrochloride salts. Vistaril, Equipose, Masmoran, Paxistil, and Vistaril Pamoate are preparations of the pamoate salt whilst Atarax, Alamon, Aterax, Durrax, Tran-Q, Orgatrax, Quiess, Vistaril Parenteral, and Tranquizine are hydroxyzine hydrochloride.

Other drugs related to hydroxyzine are cyclizine (Marezine), buclizine, and meclizine (Dramamine II) and they share all or most of the benefits, indications, contraindications, cautions, and side effects of hydroxyzine. The second-generation antihistamine cetirizine is in fact one of the metabolites of hydroxyzine produced in the human body, therefore having a narrower spectrum of effects, making it an effective antihistamine but removing some or all of the anxiolytic and analgesic-sparing properties.

Prescription and use Edit

Hydroxyzine is both an antihistamine and anxiolytic (see below) and its use as a mild tranquilliser is especially common in dentistry and it retains some popularity in obstetrics, where for many years it was especially preferred for its ability to boost the effectiveness of alphaprodine (Nisentil), a narcotic analgesic related to pethidine as well as permit later use of scopolamine or benzodiazepines better than other drugs might.

Hydroxyzine hydrochloride is distributed by several manufacturers as tablets and capsules with strengths of 12.5, 25, 50, and 100 mg. Oral liquids and ampoules and multi-dose phials for injection are also available. Less commonly, tablets of 5, 10, 20, and 30 mg are manufactured, as are 25 mg suppositories. The latter four strengths of tablets are apparently used both in human medical and vetrinary settings.

Hydroxyzine is prescribed when the onset of an organic disease state manifests through anxiety, as general anxiety disorder, or in other more serious cases as psychoneurosis, and is therefore prescribed as a means of regulating normal function. Hydroxyzine can also be used for the treatment of allergic conditions, such as chronic urticaria, atopic or contact dermatoses, and histamine-mediated pruritus. These have also been confirmed in both recent and past studies to have no adverse effects on the liver, blood, nervous system or urinary tract.

In the case of both the pamoate and hydrochloride salts, use of hydroxyzine for premedication as a sedative has no effects on belladonna alkaloids, such as atropine, but may, following general anesthesia, potentiate meperidine and barbiturates, and use in pre-anesthetic adjunctive therapy should be modified depending upon the state of the individual. Hydroxyzine is also safe to use alongside other medications or cardiac agents derived from the digitalis plant, as it does not yield any side-effects, due to its effects on the sympathetic, rather than the central nervous system.

Whilst the analgesic-sparing (potentiating) effect is most marked with pethidine and relatives in certain cases such as post-operative pain, the effect can be noticed and used with most or all opioid analgesics and other centrally-acting analgesics which are not opioids such as orphenadrine and nefopam and may also help reduce muscle spasm and set the stage for ibuprofen, naproxen, other NSAIDs, aspirin and paracetamol to work better for the patient, especially if used in conjunction with diphenhydramine (Tylenol PM, Percogesic Extra-Strength and its aspirin, naproxen, diclofenac, and ibuprofen analogues) or phenyltoloxamine (Percogesic original forumla, some extra-strength backache remedies like Momentum and Doan’s Pills)

One of the more common regimens for moderate to moderately-severe pain — be it acute, recurring acute or chronic — prescribed in the United States and Canada and some European and Asian countries is a prescription for plain codeine tablets or combination products containing paracetamol, aspirin, ibuprofen, or similar drug with codeine (Tylenol With Codeine No. 1, 2, 3 & 4, the Emprin With Codeine and 222-292-293-294 series, and many other trade names) and instructions to combine an anti-inflammatory pain reliever like ibuprofen or naproxen with it and to combine this with a prescription for hydroxyzine to be taken in dosages of 12.5 to 100 mg either along with the codeine or at a fixed schedule of its own. In the case of sports injuries, other injuries, severe sinus infections and others, another part is added to the regimen in the form of a centrally-acting non-benzodiazepine muscle relaxant such as orphenadrine (Norflex), cyclobenzaprine (Flexeril), chlorzoxazone (Parafon), baclofen (Lioresal) and others. Of course, the narcotic can be changed to hydrocodone, dihydrocodeine, ethylmorphine, tramadol, pentazocine, nicodicodeine, propiram, oxycodone, benzylmorphine, thebacon, nicocodeine, dextropropoxyphene, tilidine, meptazinol or others; they can be found alone or in preparations which contain the narcotic along with aspirin, ibuprofen, or other similar drugs with or without paracetamol. The selection of carisoprodol (Soma) as the muscle relaxant often yields a particularly powerful combination and the doses of the narcotic as well as the hydroxyzine must be cut down substantially to start the careful titration of the dose. Such cases may produce enough somnolence to require the elimination of the hydroxyzine or replacement of it with cyclizine and/or addition of caffeine to the regimen by itself or as an ingredient in the narcotic combination product.

In other cases, the usage of hydroxyzine is as a form of non-barbiturate tranquilliser used in the pre-operative sedation and treatment of neurological disorders, such as psychoneurosis and other forms of anxiety or tension states. The trade name Atarax for the hydrochloride points to this ataractic (anti-anxiety) effect and Tranquizine and Tran-Q are trade names which point to a similar spectrum of actions. Physicians and patients both often prefer hydroxyzine to benzodiazepines, babiturates, and meprobamate-glutethemide type depressants as first-line treatments for insomnia and daytime anxiety as hydroxyzine is safer, clears out of the system more quickly than many depressants like diazepam, phenobarbital, chloral hydrate and others, and does not cause physical dependence nor does it generate a morbid seek orientation for the drug in the patient.

It has been suggested through pharmacological trials that the usage of hydroxyzine on dogs reduced the incidence and duration of ventricular arrythmias, and that it is able to block the spasmogenic actions associated with other substances such as serotonin, reserpine, histamine, acetylcholine and the effect of pituitary extract on the duodenum. Similarly, in experiments conducted on the ileum of small rabbits, hydroxyzine was found to inhibit hypermotility caused by the presence of barium chloride.

For dentistry and obstetrics as well as other surgeries and procedures and acute pain situations like accidents, hydroxyzine is useful as a first line anxiolytic and opioid adjunct because it lacks both antagonism and synergy with benzodiazepines and scopolamine, allowing either of these agents to be used simultanteously or later in the procedure if need be.

Hydroxyzine is one of the least anticholinergic first-generation antihistamines at about 8-10 per cent of the antimuscarinic power of atropine. It is also, along with its relatives cyclizine, buclizine, meclizine, and others as well as phenindamine (Thephorin, Nolahist) and cyproheptadine (Periactin) (the prototype of the piperidine chemical class of first-generation antihistamines), and the phenothiazines, part of a small number of antihistamines to have clinically significant antiserotonergic effects as well.

Hydroxyzine has beneficial effects listed in this article but stands out in this pharmacotherapeutic category for its virtually non-existent addiction liability. The piperazine class of antihistamines is the fourth or even lower of the seven categories of first-generation antihistamines in the generation of euphoria in patients. The euphoria, which is mild (certainly not at the same level as morphine &c.) and tends to be either transient or long-lasting, appears to be part of the impact either direct or indirect on dopamine, acetylcholine, and possibly serotonin, norepinephrine, and even endorphin levels and ratios and possible activation of parts of the NMDA systems. Therefore, it would also stand to reason that it is reinforced by the alleviation of discomfort, much in the same way as some people experiencing transient euphoria after taking ibuprofen or naproxen. The ethanolamines (diphenhydramine, orphenadrine, dimenhydrinate, carbinoxamine and others) and alkylamines (triprolidine, pheniramine, brompheniramine, chlorpheniramine and others) are the strongest euphoriants amongst antihistamines and some ethylenediamines like pyrilamine and tripelennamine are on the list as well.

Hydroxyzine is not thought to be an effective treatment for anxiety if used for a period of over 4 months, and it is therefore a prerequisite of any medical professional prescribing such drugs, to re-assess the usefulness for the individual patient. Reasoning for this decision stems from the fact that hydroxyzine is mainly used as an antihistamine and has a somewhat short shelf-life in its common form. Rather than its use as an anxiety-reducing agent, hydroxyzine should be reconsidered if the patient has more intense anxiety or other psychoneurosis; then other compounds specifically designed for such conditions should be considered.

Treatment of learned helplessness Edit

Aside from its prescription as an antihistamine, hydroxyzine has also shown slight possibilities for use in other species, such as dogs, from results and effects observed in rats with “learned helplessness” induced through the use of random inescapable shocks (max 0.8 mA) administered in 1 minute intervals for a period of 15 seconds for an hour. After the condition was induced, rats were then given a conditioned stimulus of a light, and shocked if unable to move to safety from the area producing the current within 3 seconds. Those unable to move were determined as having a conditioned stimulus of expecting shocks from the initial random condition.

In the initial treatment to this condition, rats were given hydroxyzine as a curative treatment for the shocks received and as a treatment for the prevention of learned helplessness by injection beforehand; results indicating that beforehand, hydroxyzine decreased the overall amount of escape failures by a similar amount to those observed in diazepam, which achieved similar results, however, with side effects of amnesia. Despite the fact that hydroxyzine clearly increased the ability of the rats to avoid stimuli, it had almost no effect on the rats ability to respond to the shocks nor remove “stress” after exposure to shocks.

Clinical description Edit

Metabolisation and pharmacokinetics Edit

Hydroxyzine can be administered orally as hydroxyzine hydrochloride or hydroxyzine embonate, or via intramuscular injection as hydroxyzine hydrochloride. When given orally, hydroxyzine is rapidly absorbed from the gastro-intestinal tract. The effect of hydroxyzine is notable in 30 minutes.

Pharmacokinetically, hydroxyzine is rapidly diffused in the body and absorbed in oral and intramuscular administration, and is metabolised in the liver; the main metabolite (45%) through oxidation of the alcohol moiety to a carboxylic acid, is cetirizine and overall effects are observed within one hour of administration. It has a half-life observed on average for around 7-10 hours in adults, 6-7 hours in children, and 18-21 hours in the elderly, or those with renal insufficiency, with higher concentrations found in the skin than in the plasma. Cetirizine, although less sedating, is non-dialyzable and possesses similar anti-histaminergic properties. “In animals, hydroxyzine and its metabolites are excreted in feces via biliary elimination.” “The extent of renal excretion of VISTARIL has not been determined” Administration in geriatrics differs from the administration of hydroxyzine (pamoate or Vistaril) in younger patients; according to the FDA, there have not been significant studies made (2004), which include population groups over 65, and therefore have not provided a distinction between elderly aged patients and other younger groups: any hydroxyzine administered should be done with doses at the small end of the dosing range, and be carried out with the knowledge that any existing concomitant disease, or decrease in the function, or lessened excretion, such as the case may be with hepatic, renal or cardiac states.

Similarly, the use of sedating drugs alongside hydroxyzine can cause over-sedation and confusion if administered in large amounts—any form of treatment alongside sedatives should be done under supervision of the patient.

Contraindications Edit

The administration of hydroxyzine in large amounts by ingestion or intramuscular administration during the onset of pregnancy can cause fetal abnormalities—when administered to pregnant rats, mice and rabbits, hydroxyzine caused abnormalities with doses significantly above that of the human therapeutic range. In terms of humans, a significant dose has not yet been established in studies, and by default, the FDA has introduced contraindication guidelines in regard to hydroxyzine. Similarly, those at risk from, or showing previous signs of hypersensitivity are also contraindicated.

Other contraindications include the administration of hydroxyzine alongside depressants and other compounds which affect the central nervous system, such as narcotics, non-narcotic analgesics and barbiturates, as well as alcohol, and if absolutely necessary, should only administered concomitantly in small doses as any pre-existing grogginess from these substances may be enhanced. If administered in small doses with other substances, such as mentioned, then patients should refrain from using dangerous machinery, motor vehicles or any other practice requiring absolute concentration, in accordance with safety law.

Studies have also been conducted which show that long-term prescription of hydroxyzine can lead to tardive dyskinesia after years of use, but has also been reported after periods of 7.5 months showed effects related to dyskinesia, such as continual head rolling, lip licking and other forms of athetoid movement. In certain cases, elderly patients’ previous interactions with phenothiazine derivatives or pre-existing neuroleptic treatment may have had some contribution towards dyskinesia at the administration of hydroxyzine due to hypersensitivity caused due to the prolonged treatment, and therefore some contraindication is given to the short-term administration of hydroxyzine to those with previous phenothiazine use.

Adverse reactions Edit

For a full list of side effects, consult the full technical specification of hydroxyzine.

Several reactions have been noted in manufacturer guidelines for two forms of hydroxyzine: Atarax and Vistaril. In Atarax, symptoms are similar to those of Vistaril — deep sleep, incoordination and dizziness have been reported, as in children and adults, as well as others such as hypotension, tinnitus and headaches. Gastro-intestinal effects have also been observed in both Visatril and Atarax, as well as less serious effects such as dryness of the mouth, constipation caused by antimuscarinic properties of hydroxyzine.

Central nervous system problems such as hallucinations or confusion have been observed in rare cases, attributed mostly to overdosage. Such properties have been attributed to hydroxyzine in several cases, particularly in patients treated for neuropsychological disorders, as well as in cases where overdoses have been observed. While there are reports of the “hallucinogenic” or “hypnotic” properties of hydroxyzine, several clinical data trials have not reported such side effects from the sole consumption of hydroxyzine, but rather, have described its overall calming effect described through the stimulation of areas within the formatio reticularis. The description of hallucinogenic or hypnotic properties have been described as being an additional effect from overall central nervous system suppression by other CNS agents, such as Lithium or Alcohol.

The effect of hydroxyzine has also been tested on the ability of humans in the registration and storage of memory, and was used in comparison with relatively safe drugs, such as hydroxyzine, to illustrate the effects of benzodiazepines, which are thought to have adverse effects on the capacity of memory storage. Hydroxyzine was found to have no adverse effects on memory in relation to lorazepam, which caused several deficiencies in the capacity of memory storage.

In a comparative study with lorazepam on memory effects, patients who had taken hydroxyzine experienced sedative effects similar to drowsiness, but recalled that they felt capable, attentive and able to continue with a memory test under these conditions. Conversely, those under the effects of lorazepam felt unable to continue due to the fact they felt out of control with its effects; 8 out of 10 patients describing tendencies of problems with balance and control of simple motor functions.

Severe somnolence with or without vivid dreams or nightmares may occur in users with antihistamine sensitivities or other CNS depressants available in their systems. Hydroxyzine exhibits very potent anxiolytic and sedative properties in many psychiatric patients. Other studies have suggested that hydroxyzine acts as an acute hypnotic, reducing sleep onset latency and reciprocal increases in sleep duration — also showing that some drowsiness did occur, but in female patients who also had greater hypnotic response. It did not, however, show any significant or noticeable effect of drowsiness, other than in female patients’ subjective responses.

Some users may report shortness of breath or wheezing, a result of a mild allergic reaction to the medication itself.

In contrast to drugs in the benzodiazepine class, (i.e. alprazolam, diazepam) which carry a potential for abuse and dependence, hydroxyzine is very unlikely to cause any dependence due to its relative strength compared to other substances.

See alsoEdit

  • Antihistaminic drugs

References Edit

Notes Edit

Print sources Edit

Internet-based Edit

  • RxList , et al. Atarax Indications, Dosage, Storage, Stability. RxList – The internet drug index. URL accessed on 2007-03-09.
  • Medscape Vistaril Oral: Monograph – Hydroxyzine Hydrochloride, Hydroxyzine Pamoate. medscape.com. URL accessed on 2007-03-09.
  • pfizer Non-print version of vistaril fact sheet.. URL accessed on 2007-07-03.

Drug information pamphlets Edit

  • UCB South-Africa, et al., (2004). ATERAX 25 mg TABLETS; ATERAX 100 mg TABLETS; ATERAX SYRUP (Manufacturing guidance package insert) Pharmacare Ltd, (a division of Aspen Pharmacare Ltd)

This box: view • talk • edit Psycholeptics: anxiolytics (N05B)


Diazepam – Chlordiazepoxide – Medazepam – Oxazepam – Potassium clorazepate – Lorazepam – Adinazolam – Bromazepam – Clobazam – Ketazolam – Prazepam – Alprazolam – Halazepam – Pinazepam – Camazepam – Nordazepam – Fludiazepam – Ethyl loflazepate – Etizolam – Clotiazepam – Cloxazolam – Tofisopam


Hydroxyzine – Captodiame


Meprobamate – Emylcamate – Mebutamate



Azaspirodecanedione (serotonin receptor agonist)

Buspirone – Gepirone – Tandospirone


Mephenoxalone – Gedocarnil – Etifoxine


Some patients report a decrease in interstitial cystitis (IC) symptoms using other antihistamines or medicines with antihistamine properties. Though the most widely used antihistamine to treat IC is hydroxyzine, some people with IC find relieve from Claritin, Benadryl, and Singulair.

A mild anti-anxiety drug, hydroxyzine is available in two oral forms:

  • Hydroxyzine pamoate (Vistaril)
  • Hydroxyzine hydrochloride (Atarax)

Hydroxyzine affects mast cell degranulation, which is thought to play a part in some IC patients’ symptoms, especially those who have a history of allergies, migraines and irritable bowel syndrome. Hydroxyzine has been shown to improve these conditions, as well as IC. Hydroxyzine has been found to decrease:

  • Nocturia (night time voiding)
  • Daytime frequency
  • Pain (burning, pressure, painful intercourse)

Hydroxyzine pamoate has a slightly higher absorption rate. Hydroxyzine-HCL is a liquid form available for patients allergic to fillers or dyes used in the capsules or pills.

Dosage & Treatment Plan

Most patients start with a 10 to 25 milligram (mg) dosage of Atarax, Vistaril or their generic equivalent at bedtime every night for 1 week, and progress to 50 mg every night the second week. Ideally, within one month the dosage is increased to 75 mg, 50 mg taken at night and 25 mg taken during the day. Benefits of hydroxyzine may be seen within a few weeks to two months after initiating therapy.

To decrease the sedating side effects, some patients start hydroxyzine therapy at a 10 mg dosage, available with Atarax or in the liquid form, and work their way up, gradually, to a maximum dosage of 50 to 75 mg. After one year some patients are able to decrease their dosage by one-half without increasing symptoms. Others report that upon reducing their dosage, symptoms will return within a few days.

Potential Side Effects

Side effects include sedation, dry mouth, and increased depression in patients diagnosed with concurrent depression.

Take this medicine early in the evening initially to avoid excessive morning drowsiness. Most patients report that daytime drowsiness disappears within four to five days after beginning hydroxyzine therapy. Some patients report that with each dosage increase, the drowsiness period is shorter and not as intense.

Pregnancy & Warnings

Animal studies have found that fetal abnormalities occur at doses ten times higher than given to humans. It is not recommended that hydroxyzine be used if pregnant or nursing. Hydroxyzine is contraindicated for use in epileptic patients.

Revised Wednesday, March 25th, 2015

(385) The Evaluation of Blended Codeine Phosphate with Hydroxyzine Pamoate, Gabapentin, Ondansetron, and Docusate for the Treatment of Chronic Pain: A Patient-Centered Approach to the Pain Management “State of Emergency”

The United States is suffering from a so-called opioid epidemic. It has been proposed that the onset of this epidemic occurs in physician offices. In November 2016, the Centers for Disease Control published guidelines for the treatment of non-cancer related pain. In this guideline, they suggested limitations as to the amount of morphine milligram equivalencies that are allowed for adequate pain relief, while limiting the complication rate. In this study, we evaluate the effectiveness of a Codeine preparation for the treatment of moderate to severe pain. The study evaluates the effectiveness of reducing MME through substituting medication with a low MME rather than weaning the patient. A trial of 20 patients was carried out. The patients were required to score their pain while on their previous medications. The score was the standardized one -10/10 methodology. The patients were then switched to a Codeine blended therapy and were asked to report on their pain, using the same methodology. The effectiveness of this treatment program is presented. P values are calculated. Of the 20 patients, 19 had excellent results with equal pain relief and no significant adverse reactions. The use of a blended codeine therapy can lower the MME without change in pain or withdrawal.

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