Why do antidepressants make you tired?

Antidepressants and sleep

By Dr Simon Kyle

How do antidepressants affect sleep?
Antidepressants are principally prescribed for the treatment of clinical depression. However, given the strong bi-directional relationship between depression and insomnia, several research studies have assessed the effects of antidepressants on sleep continuity (sleep onset, wake after sleep onset, total sleep time, and sleep efficiency) and sleep architecture (stages of sleep). Indeed, many clinicians will often give out off-label prescriptions of antidepressants for poor sleep, rather than sleeping pills, due to the perception that they are less habit-forming – and so can be taken for longer – and that they have less potential for side-effects. It is important to note, however, that rigorous controlled trials of antidepressants for the effective treatment of insomnia are lacking and that current guidelines do not endorse their widespread use.
The extent to which an antidepressant will affect sleep is ultimately determined by the class of antidepressant being prescribed. This will influence the resultant pharmacologic effects on brain neurotransmitters like serotonin and noradrenaline, and receptor sites including histamine, serotonin, and adrenergic receptors. It is also important to note that effects on sleep can vary between and within classes of antidepressant medications, and will depend on whether one studies healthy participants or those with clinical depression (Wilson & Argyropoulou, 2005; Mayers & Baldwin, 2005).
In general, antidepressants tend to suppress REM sleep and increase the time taken to enter REM sleep. Both increased REM sleep density and reduced latency to REM sleep are characteristic of patients with depression and thus antidepressants appear to normalize these parameters. Indeed the amount to which antidepressants suppress REM sleep has been associated with enhanced overall antidepressant response (less severe depression symptoms). In some studies, selective serotonin reuptake inhibitors (SSRIs), like sertraline and fluoxetine, have been shown to disturb/fragment sleep. Tricyclic antidepressants (TCAs), like amitryptiline, and serotonin antagonist and reuptake inhibitors (SARIs), like trazadone, have been shown to have a sedative effect, improving sleep continuity and quality. Effective antidepressant treatment response, where mood is improved, may often be accompanied by improved subjective ratings of sleep; however, recent research data also suggest that poor sleep can frequently emerge as a consequence of antidepressant treatment, remaining even after successful remission of depression.
You should always consult your doctor for advice on medication – starting, changing or finishing a course of medication can have serious effects. Ensure that you consult your GP if you have any questions on this.

Filed under: Sleep aids

Why does depression make you feel tired?

Share on PinterestFatigue is a common symptom of depression.

People with depression are more likely to experience fatigue, and people with chronic fatigue are more likely to become depressed, creating a cycle that can be hard to break.

Potential causes of depression fatigue include sleep problems, diet, stress, and even the medications used to treat depression.

Learn more about each cause below:

Sleep problems

Sleep is essential for regenerating the body and replenishing energy. Lack of sleep alone may not cause depression, but it does increase risk and can make existing depression symptoms worse.

Even if a person with depression is getting enough sleep, they may not wake up feeling refreshed because the quality of sleep is often lower than that experienced by a person who does not have depression.

Research shows that many people with depression and other mental health conditions, such as bipolar disorder, experience both insomnia and hypersomnia.

Insomnia means having trouble falling asleep or staying asleep. Hypersomnia refers to excessive sleepiness.

Obstructive sleep apnea is another sleep disorder that has links with depression. One 2015 study found that depression is common in people with sleep apnea and that it affects the severity of sleep apnea.

Furthermore, the study found that treating the sleep apnea improved depression symptoms.


Researchers have long speculated about whether diet affects mental health. One recent meta-analysis looked at multiple studies for a link between diet and depression risk.

The report found some evidence that higher quality diets, such as those that include anti-inflammatory foods, may lower some people’s risk for depression. However, more research needs to be done

A second meta-analysis also associated specific diet patterns with an increased risk for depression. In particular, researchers found that Western-style diets containing red meat, processed meats, refined grains, sweets, and other unhealthful foods may increase the risk for symptoms of depression in some people.


Share on PinterestStressful life events can contribute to depression.

Stress can affect levels of serotonin and dopamine, which are chemicals in the brain that play an essential part in regulating mood and energy.

Research indicates that stressful life events can significantly increase a person’s risk of developing major depressive disorder.

These stressful life events can include the end of a relationship or close friendship, death of a loved one, significant financial loss, job changes, and health-related events, such as a cancer diagnosis.

The same research suggests that stress can also cause inflammation in the body, which can lead to hypersomnia and fatigue. It may also cause a person to withdraw from social activities and have problems thinking clearly.


Antidepressants work by acting on the brain’s neurotransmitters to help them do a better job of regulating a person’s mood. Some antidepressants, however, can cause significant fatigue.

5 Things that Sometimes Happen When You’re On Prozac

One in ten people in the United States are on antidepressants. Depression is a serious issue and I’ve written an article about it before, but I thought that it would be a good idea to write something more lighthearted in hopes that it would help change the conversation about mental illness towards a less gloomy direction. Now, there are numerous side effects when it comes to Prozac and also a lot of variation when it comes to individual experience, but hopefully some you can relate to this and laugh a little.

1. Shi* gets real in your dreams.

I don’t know how prevalent this side-effect of Prozac is, but this happens to me big time. There isn’t much research and data on why Prozac tends to give people extremely vivid dreams, but a quick Google search turns up numerous chat forums of people talking about it, which tells me that it isn’t a coincidence. Before getting on antidepressants, I almost never remembered my dreams, but now literally everything is burned onto my mind. According to my psychiatrist, Prozac doesn’t actually cause vivid dreams but makes you more able to recall your dreams. So you’re still dreaming the same way you have been all your life, the difference is that you can now remember them after you wake up. I’ll have to admit it’s more than a little disturbing to discover what my subconscious cooks up in my sleep. I’ve gone from chasing dragons with Khaleesi to baking pastries with Mung Daal.

2. Your tolerance becomes nonexistent.

You used to be able to handle your alcohol in a decent manner. But now, oh boy, you are now the one-shot-wonder. Every time you’re drinking with friends, they give you hell for sipping on a 90 percent mixer and 10 percent liquor concoction all night. You have to frequently remind them that two shots for them gets them buzzed but gets you horizontal.

3. You sometimes have no idea whether you took your meds for the day.

Me : I’m pretty sure I did.

Brain : Nah man, you’re thinking about yesterday. Did you do it today?

Me : I did! Or wait, did I just dream of doing it?

Brain : Probably not, we dreamt about turning into a coffee bean last night, remember?

Me : Right, okay, so I’ll take it now.

Brain : WAIT! What if you actually took it, isn’t it bad to overdose?

Me : But if I don’t take it, that’s going to mess up the whole neurotransmitter thingamajiggy.

Brain : What if we compromise and you just take half?

Me : I don’t think it works that way…

4. You forget to bring your pill bottle on a trip and feel doomed.

This has happened to be a handful of times, and even though I once read something about how Prozac has a relatively long shelf life, I’m almost certain that each time there’s been a significant dip in my mental state. Maybe it’s the Placebo effect. Whenever I haven’t taken my meds for a few days and feel even remotely depressed, I freak out and blame it on the lack of medication even though I’m probably almost always just fine.

5. You are sleepy and alert at all the wrong times.

I frequently had trouble sleeping growing up, so this was nothing too new. Once I got to high school and college my sleeping pattern evened out pretty well, likely because I was so tired at the end of every day that I could pass out really easily. After starting my antidepressants, however, I would occasionally either not be able to sleep for hours or sleep for 12 hours straight. Some nights I would lie awake for hours and end up staring at my tortoise in hopes that it would make me sleepy, and on some mornings, I would wake up five hours later than I was supposed to and not know what was happening in the world.

Joking aside, side effects are a legitimate cause for concern, and antidepressants should only be taken if they are outweighed by the benefits you get from them. For me, none of these are actually that bad; I have a ton of great icebreakers in the form of bizarre dreams and I get to hog the TV while my roommate is alseep!

Your 10 Biggest Antidepressant Problems, Solved

1. ‘Ugh. Suddenly my head hurts.’

During the first few days on your new prescription, you might find that you have a headache. All antidepressants have the potential to give you a headache for a few days, says psychiatrist Boadie Dunlop, MD, associate professor of psychiatry and behavioral sciences and director of the mood and anxiety disorders program at the Emory University School of Medicine in Atlanta.

RELATED: 6 Things I Didn’t Know About Depression Until It Happened to Me

He suggests taking Tylenol (acetaminophen) to help, adding that this symptom usually gets better within the first week or two.

2. ‘My stomach is upset, and I have diarrhea.’

People taking SSRI antidepressants (selective serotonin reuptake inhibitors) might find that they have nausea, diarrhea, or constipation. You can manage nausea by taking the medications with food, Dr. Dunlop says.

Make sure you’re eating enough fiber and drinking enough fluids; you also might consider taking an over-the-counter medication for constipation or diarrhea. Like headaches, these symptoms typically go away early in your treatment.

3. ‘I have the shakes.’

A small number of people find that their medication causes shakiness or tremors. “These can persist and can prevent people from continuing with their medication,” Dunlop says. If you develop this symptom, contact your doctor to discuss changing your dose, or the drug itself.

4. ‘I’m still sad.’

Of all antidepressant problems, this may be the thorniest to untangle. If you’re continuing to experience depression symptoms despite taking an antidepressant, there are a number of possible explanations to consider:

  • You got the wrong diagnosis. “When someone has depression that doesn’t respond to treatment, the first thing you do is step back and make sure you have the right diagnosis,” Dr. Combs says. Your psychiatrist might want to do more tests to make sure some important clues weren’t missed the first time around.
  • Your medication hasn’t kicked in yet. Sometimes it takes time for antidepressants to become effective. Check with your doctor to find out whether you need to wait a bit longer.
  • You’re drinking alcohol or using drugs. These substances can interfere with your depression treatment, so you’ll need to quit if you want complete success.
  • You’re not in therapy. It would be nice if medication could solve all depression problems, but you might also need to talk with a therapist to help you figure out how to cope with issues in your life that are causing you to feel sad or anxious.
  • You’re taking the wrong medication. You might find relief by switching antidepressants or adding another medication, such as a thyroid drug or lithium. Talk about this with your doctor.
  • You need to try something new. Ask your doctor whether you might benefit from other approaches — even unconventional ones. For example, dance movement therapy has been shown to help manage depression, according to research published in Frontiers in Psychology in 2015.

5. ‘I’m not sad, but I’m not happy either.’

Anywhere from 28 to 60 percent of people who take antidepressant medication experience emotional blunting — a feeling of being depleted of all emotions, including the good ones, according to research published in 2013 in the International Journal of Neuropsychopharmacology.

But you don’t have to lose your ability to feel joy just to get rid of the pain: Emotional blunting is best resolved by switching to a different class of antidepressants, adding a second medication, or talking with a therapist, Combs says.

6. ‘My antidepressant is making me fat.’

Some depression treatments, notably those that involve a combination of drugs, do put you at risk for weight gain, according to a review from 2015 in Expert Opinion on Drug Safety. Taking Lexapro (escitalopram) and Wellbutrin (bupropion) together, for instance, showed a greater likelihood of an increase in body mass index (BMI) than single-drug therapy, according to a study published in 2015 in Therapeutic Advances in Psychopharmacology.

RELATED: How Yoga Helps With Depression, Anxiety, and Addiction

If you have a history of being overweight, you’re more likely to gain while on an antidepressant — “so choose an antidepressant that is weight-neutral,” Combs advises. If that’s not an option, she emphasizes getting counseled in diet and exercise. An added bonus? The National Institute of Mental Health (NIMH) notes that exercise can be an important part of your treatment.

7. ‘Sex tonight? No way!’

Many people struggling with depression lose interest in sexual activity, but some antidepressants can also make it difficult to respond sexually. Doctors don’t always warn their patients about this effect, Combs says, and it can be very frustrating. Some people are willing to accept it as a temporary trade-off for successful depression treatment, but most people want solutions.

Consider switching antidepressants, trying a different dosing schedule, taking other medications to improve sexual response, or experimenting with new ways to increase arousal. Testosterone might be a solution for some people who have lost some interest in sex but need to stay on their antidepressant medication, according to research published in 2014 in The Journal of Sexual Medicine.

8. ‘I’m up all night.’

Insomnia, sleeping too much, and other changes to your sleep cycle are all signs of depression, according to the NIMH. And when you can’t get a good night’s sleep, it can make it even harder to treat your depression effectively.

“Some antidepressants are identified as activating, and some are sedating,” Combs explains. Finding the right match for you is key. A sedating antidepressant, for instance, might be a good bet for someone who is having problems falling asleep. It’s also important to look at other lifestyle choices that might be affecting your sleep, like your environment, physical activity (or lack of it), caffeine consumption late in the day, napping during the day, and alcohol use.

9. ‘I want to stop taking my meds — but I’m afraid my depression will come back.’

Once you start feeling better, you’ll probably want to quit taking antidepressants — but, Dunlop says, you need to be stable on antidepressants for at least six months first, to reduce the risk of experiencing another bout of depression in the future.

Although antidepressants are only temporary for most people, you should never stop taking them (or any prescription medication) without the guidance of a doctor. Usually the best approach is to reduce the dosage very gradually — stopping “cold turkey” could result in unwanted side effects, Dunlop adds.

10. ‘I want to die.’

With depression, there’s always a risk of suicidal thoughts, but these can also be a side effect of antidepressants, though a rare one. A Finnish study published in 2014 in Human Psychopharmacology found that the risk for suicide is not significantly increased by the use of antidepressants, although other factors of depression, such as insomnia, do contribute to suicide risk.

Regardless of what might be prompting suicidal thoughts, call your doctor immediately if you start to experience worsening depression symptoms, including suicidal thoughts or thoughts of harming yourself or others, Dunlop advises.

If you’re running into a problem with your antidepressants, there’s likely a solution — so don’t ignore it. Get to the bottom of it.

When a series of difficult family and financial issues simultaneously came to a head, 43-year-old Suzanne* began to feel herself spiraling down into a dark and seemingly inescapable place in her mind that she suspected was true depression. A visit to a psychiatrist confirmed her suspicions and together she and the doctor agreed that antidepressant medication was necessary at that time. The psychiatrist prescribed Lexapro, and within just a couple of weeks of taking the first pill, Suzanne began to feel more hopeful and more like her old self again. Throughout the 18 months she took Lexapro, her mental outlook improved and remained healthy so she was able to work with a psychotherapist and learn to cope with what had felt like overwhelming personal circumstances. Her life improved.

Not so for 16-year old Coralie*, who struggled with severe anxiety and panic attacks in high school and was also prescribed Lexapro. Within two weeks of starting medication, instead of feeling better, her mood became darker and darker. Soon Coralie began to have suicidal thoughts. She never acted on those thoughts, but after they become powerful enough to land her in the emergency room, she stopped taking Lexapro, and her parents sought new treatment that involved more intensive psychotherapy.

“Most people feel better with antidepressants but, for some—especially those under the age of 25 and those with bipolar depression—these drugs can make mental disturbances feel even worse,” says Psycom Editorial Board Advisor Chris Aiken, MD. Dr. Aiken is also the director of the Mood Treatment Centers in western North Carolina and editor-in-chief of The Carlat Psychiatry Report. “Keep in close contact with your doctor if you’re not feeling better or you actually feel worse, because it can be difficult for you to tell if such a response is the sign of a serious reaction or simply a side effect that is harmless and will go away with time,” he says.

How Does Lexapro Work?

Neither depression nor the activity of antidepressant medications, are fully understood. Depression has long been associated with lower-than-normal levels of a neurotransmitter, or chemical messenger in the brain, known as serotonin. Normally, serotonin helps transport messages from one neuron (brain cell) to another, then moves on and is recycled, so that messaging can be continued. Like other SSRI antidepressants, Lexapro slows down this process, which increases the amount of serotonin available to brain cells at any given time and correcting what is thought to be a chemical imbalance. Newer research suggests that this increase of serotonin, over time, alters other brain systems as well and that those alterations are actually responsible for improvements in mood.

“Lexapro raises the levels of neuroprotective compounds in the brain,” Dr. Aiken adds. “These compounds help cells located in the mood center of the brain to grow and strengthen, resulting in improved connections and communication between brain cells.”

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Depression is also viewed as an inflammatory condition, and some research suggests that SSRIs work because they have anti-inflammatory properties. However, other research suggests that some SSRIs are not effective in people whose blood contains markers or indicators of inflammation. 1,2 These types of conflicting results help medical experts understand why and how some types of antidepressant medications may work for some people but not for others.

For what specific conditions is Lexapro prescribed?

Lexapro is classified as an antidepressant commonly used to treat major depressive disorders and generalized anxiety disorder. At their discretion, physicians may prescribe Lexapro for other conditions, including panic disorder, social phobia, obsessive-compulsive disorder, bulimia, and post-traumatic stress disorder.

What is a typical dose of Lexapro?

The standard initial dose of Lexapro is usually 10 mg, once daily, in the morning or evening, with or without food. If Lexapro makes you feel drowsy, it is a good idea to take it in the evening. In some cases, doctors will have a patient graduate to a higher dose. It can take three to six weeks to start feeling the effects of Lexapro, although some people respond sooner.

If you forget to take Lexapro, take your missed dose as soon as you remember. But if it’s almost time for your next dose, skip the missed dose and get back on schedule. Don’t take a double dose and don’t take more than your prescribed amount of Lexapro in any 24-hour period of time.

Can anyone take Lexapro?

Lexapro may be prescribed for adults and some adolescents, however, SSRIs are not recommended for use in all young people, due to an increased risk of suicidal thoughts and behavior in some children and young adults. The risk is especially high in those who have previously experienced suicidal thought or behaviors. Young people, their families, and caregivers should be aware of this risk and discuss any concerns with the prescribing physician, who can best determine if the benefits of taking Lexapro outweigh the risks.3

Before starting Lexapro treatment, be sure your doctor knows about any other physical or mental health conditions you have, as well as any prescription or over-the-counter medications, supplements, or herbal products you use to treat any medical or psychological condition, including other antidepressant treatments.

“Even a ‘natural’ product like St. John’s Wort can cause serious problems when taken with an SSRI,” warns Dr. Aiken. “The combination can cause a rare but serious condition known as Serotonin Syndrome, with side effects like muscle jerks, racing heart, confusion, mood swings, gastrointestinal distress and other symptoms that result from too much serotonin in the brain.”

It is also important to tell your doctor if you have experienced allergic reactions to drugs similar to Lexapro or to any other type of drug or substance in the past. This information will help your doctor determine if it is safe for you to take Lexapro. Be aware that dangerous and potentially life-threatening reactions can occur with the use of Lexapro, especially when combined with other drugs.

Genetic testing may help determine whether or not Lexapro is the right medication for you, though the results are not always 100% accurate and the tests are not always covered by health insurance plans because evidence-based recommendations and testing standards have yet to be established. 4 Medical testing for markers of inflammation, also not yet a common practice in psychiatry, might also help narrow down your best choices for antidepressant medication. Speak to your health care providers if you are interested in pursuing these types of tests.

Are there side effects associated with taking Lexapro?

Anyone taking Lexapro or another SSRI should be closely supervised by an MD and monitored for side effects. The doctor should be notified if mood does not improve after a specified time or appears to worsen at any time. Other side effects that should be reported immediately to the prescribing doctor include:

  • Nervousness
  • Grouchiness
  • Restlessness
  • Feelings of panic
  • Hyperactivity
  • Paranoias
  • Hallucinations
  • Confusion
  • Any changes in mood or behavior
  • Increased heartbeat
  • Muscle stiffness
  • Fever
  • Nausea, diarrhea or vomiting
  • Changes in blood pressure
  • Loss of physical coordination

“SSRIs can also have blood-thinning effects,” Dr. Aiken points out, “so you may notice an increase in menstrual flow or other types of bleeding, and you may have to stop taking them if you are having surgery.”

Is it OK to suddenly stop taking Lexapro?

Always check first with your prescribing physician before you stop taking Lexapro, or change your dose. It is important to gradually taper off medications like Lexapro, and to watch for withdrawal symptoms while decreasing your dose. These symptoms—which may not be dangerous but can be very unpleasant—include dizziness, anxiety, insomnia, emotional instability, and sensations of electrical shock (“brain zaps”). If withdrawal symptoms are severe, your doctor may need to increase your reduced dose slightly and then prescribe a more gradual reduction.

Medically reviewed by Chris Aiken, MD

*Names changed to protect the privacy of the real patients who shared their stories with Psycom

Article Sources Last Updated: Jun 12, 2019

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