Prozac Making You Tired? Learn More About Antidepressant Fatigue (2024)

Depression can be exhausting. Fatigue is a common symptom of this condition, but it turns out that it can be a side effect of the treatment as well. Antidepressants can be an important part of a treatment plan, but it's important to recognize that they can also leave you feeling tired or sleepy.

Luckily, many of the side effects of antidepressants tend to subside as your body adjusts to the medication. Until that happens, however, it can be helpful to know what to expect and how to handle the feelings of fatigue that you might experience.

Whether you're taking selective serotonin reuptake inhibitors (SSRI) such as Prozac (fluoxetine) or serotonin and norepinephrine reuptake inhibitors (SNRI) such as Cymbalta (duloxetine), you may notice your energy levels feel much lower than usual.

Which Antidepressants Cause Fatigue?

Fatigue is a common side effect of an older class of antidepressants known astricyclic antidepressants. They include:

• Asendin (amoxapine)
• Elavil (amitriptyline)
• Norpramin (desipramine)
• Tofranil (imipramine)

However, doctors don't often prescribe tricyclic antidepressants due to their other side effects, which include disorientation or confusion, increased heart rate, and the increased risk of seizures in people who already have seizures.

But, even the newer classes of antidepressants—including SSRIs and SNRIs—often cause fatigue. Some of the major SSRIs that cause fatigue include:

• Aropax, Brisdelle, Paxil (paroxetine)
• Celexa (citalopram)
• Lexapro (escitalopram)
  
• Prozac (fluoxetine)
• Remeron (mirtazapine)
• Zoloft (sertraline)
  

Some of the major SNRIs that cause fatigue include:

• Cymbalta (duloxetine)
• Effexor (venlafaxine)
• Fetzima (levomilnacipran)
• Pristiq (desvenlafaxine)

Monoamine oxidase inhibitors (MAOIs) are another type of antidepressant. While they're generally not the first to be prescribed (as newer classes of medications generally produce fewer side effects), a doctor may prescribe an MAOI if other antidepressants aren't working.

MAOIs that may cause fatigue include:

• Emsam (selegiline)
• Marplan (isocarboxazid)
  
• Nardil (phenelzine)
• Parnate (tranylcypromine)

Wellbutrin (bupropion) is another type of antidepressant known as a norepinephrine and dopamine reuptake inhibitor (NDRI). Wellbutrin may also cause fatigue.

Why Do Antidepressants Cause Fatigue?

Certain antidepressants work by acting on brain chemicals called neurotransmitters—in particular norepinephrine and serotonin—causing them to linger in the spaces between nerve cells where they carry out their job of regulating mood.

At the same time, these medications affect other neurotransmitters, including histamine and acetylcholine, sometimes leading to unpleasant side effects such asdry mouth,blurry vision, weight gain, and sedation.

It's that last side effect—sedation—that may be responsible for the fatigue you experience when you take an antidepressant.

What to Avoid If Your Antidepressant Causes Fatigue

If you're truly fighting to keep your eyes open, there are some important things to avoid doing. Excessive daytime fatigue can be dangerous if you don't take precautions.

Steer clear of alcohol and any medications that also tend to be sedating. The combo of either with your antidepressant could make your fatigue worse.

How to Cope With Antidepressant Fatigue

You may be tempted to give in to exhaustion and set up camp on your couch, but there are other things you can do if your antidepressant is wiping you out. Here are some possibilities.

Sleep Hygiene

Research suggests that having good sleep hygiene plays a big role in combatting fatigue excessive daytime sleepiness. This means not napping during the day if you can help it (so that you're tired at night and ready for a full night's rest), and avoiding electronic devices a couple of hours before bed.

Of course, if you're extremely tired, you may find it beneficial to take a quick nap. The National Sleep Foundation advises that the optimal length of a nap for adults is about 20 minutes and no more than 30 minutes (Napping too long may make you groggier).

Exercise

Get some exercise. It sounds counterintuitive—how could moving possibly be helpful when it's the last thing you feel like doing?

So, the next time your fatigue is getting the better of you, try going for a walk around your neighborhood or doing a low-impact exercise like yoga or swimming.

Take Medications at Night

You may be able to use fatigue to your advantage by taking your antidepressant at night.

First, check with a doctor to be sure that it's OK for you to take your medication at night; but, taking it at night may help you fall asleep more easily—you'll get the rest you need to feel more alert during waking hours.

Give It Time

Typically, fatigue from antidepressants lasts for a few weeks after you start taking the medication. For most people, the side effects of antidepressants wear off as their bodies become adjusted to the medication.

A doctor will likely have you check back in with them after the first few weeks of taking the antidepressant to see if the fatigue continues. If it does, a doctor can formulate a solution for your excessive fatigue—either by changing your dosage or changing your prescription altogether.

When to See a Doctor

It's best to report any side effects of antidepressants that you're experiencing to a doctor right away. They may tell you to check in after two to three weeks to see if the fatigue you're experiencing has reduced.

If your fatigue hasn't improved after a few weeks, a doctor may lessen your dosage or prescribe a slower release preparation of antidepressant.

Or, a doctor may have you try a different antidepressant altogether. Because there is no one-size fits all antidepressant, it may take some trial and error before you and a doctor are able to find a medication and dosage that work best.

In some cases, a doctor may supplement your medication with a second drug that's stimulating, such as Provigil (modafinil). However, there are additional side effects linked with stimulant use that include:

• Diarrhea
• Dry mouth
• Eye pain
• Gas
  
• Headache
• Loss of appetite
• Muscle shaking
• Nausea
• Nosebleeds
• Sleep problems

More serious side effects of Provigil include rash, blisters, mouth sores, hives, difficulty breathing, frenzied mood, chest pain, hallucinations, anxiety, depression, and suicidal ideation. Be sure to contact a doctor if you experience these or any other side effects.

Because antidepressants and stimulants increase serotonin levels, in rare cases, taking both types of medications together may result in serotonin syndrome. Symptoms of serotonin syndrome include agitation, restlessness, hyperthermia, nausea, vomiting, tremors, muscle rigidity and more.

Most cases of serotonin syndrome are successfully treated by discontinuing the medications causing the illness. Benzodiazepines are sometimes used to treat symptoms like tremors. Cyproheptadine may also be used as an antidote.

If you're experiencing any symptoms of serotonin syndrome, be sure to contact a doctor immediately or call emergency services. Moderate to severe cases require hospitalization.

Keep in Mind

You're not alone if you find the side effects of antidepressants frustrating to deal with. But remember to always consult with a doctor before making any changes to your current dosage. Under a doctor's supervision, you may try out different dosages, medications, and sometimes, combinations of medications to alleviate your symptoms.

Try not to lose hope. In the meantime, you may find that other types of treatment—such as therapy, a support group, and healthy lifestyle changes—may promote optimal health as you search for the right antidepressant for you.