Prozac vs. Lexapro: Side Effects, Interactions, More

Medically Reviewed by Smitha Bhandari, MD on August 25, 2022
4 min read

If you, or someone you love, has a mental health disorder like depression or anxiety, medication is probably part of the overall treatment plan. Two common drugs that can help are fluoxetine (Prozac) and escitalopram (Lexapro).

There are some things you should know about each of them.

Both Lexapro and Prozac can treat many different mental health problems. Prozac has FDA approval to treat:

Lexapro can help with:


Both drugs help your body make more of a hormone called serotonin. It helps regulate your mood, feeling of well-being, and sense of happiness. It also assists with things like sleep, digestion, and appetite.

Prozac and Lexapro belong to a group of drugs called selective serotonin reuptake inhibitors (SSRIs.) These kinds of drugs make more serotonin available so that your nervous system cells can communicate better. The drugs are “selective” because they specifically target serotonin.

All drugs come with potential side effects, but that doesn’t mean you'll have them.

Lexapro can cause:

Prozac has similar side effects, but can also cause:

These generally go away as your body gets used to taking either drug. Both meds can also cause longer-term problems with sexual health. And they can cause some rare side effects, like low sodium levels or a higher chance of bleeding.

Both drugs are available as meds that you take by mouth, generally every day.

Lexapro is available in tablet form in strengths of 5 milligrams (mg), 10 mg, and 20 mg. It's also available in liquid form at 1 mg per milliliter (ml).

Prozac is available in capsule form at strengths of 10 mg, 20 mg, or 40 mg. It is also available in a liquid form at 20 mg per 5 ml.

There is also a delayed release “weekly” form of Prozac available at a strength of 90 mg.

Both Lexapro and Prozac can cause issues with several medications. So make sure you tell your doctor about all the meds that you take.

Avoid taking these drugs with certain medicines to treat depression, anxiety, or psychosis. Drugs for sleep disturbances and medications for blood clotting issues can also cause interactions.

You shouldn't use alcohol while taking either of these drugs.

It's also important to keep in mind that when you take two antidepressants together, a condition called serotonin syndrome can happen. It’s a serious problem that can bring:

Certain supplements like, St. John’s wort, and some drugs used to treat headaches can also cause serotonin syndrome when paired with an antidepressant.

There are some other important things that you should keep in mind if you're taking either of these drugs.

If you’re thinking about becoming pregnant, there are some risks to the fetus, such as low birth weight or premature delivery, if you take either of these drugs.

Don’t stop taking either drug suddenly -- even if you feel better. That may cause withdrawal symptoms like nausea and nightmares. Stopping or missing doses can also cause symptoms of your mental health issue to come back.

People under 25 have a higher chance of suicidal thoughts or behavior when taking antidepressants like Lexapro or Prozac. This usually happens in the first few weeks of treatment, or when the dose is changed.

How much you'll pay for Lexapro or Prozac depends on many things, including your health insurance coverage. But both drugs are available in generic form.

Generic versions of drugs are much less expensive than name brands. Because they are less expensive than name brands, generic versions also help people stay on their medications.

Talk to your doctor about the generic versions of these drugs and whether they're right for you.

Before taking either of these drugs, you and your doctor should discuss the symptoms that cause you the most problems, and other medications you've taken in the past to help.

You should also discuss whether you have had thoughts of suicide or of harming yourself. Also, ask your doctor about any nonmedical treatment, such as talk therapy, that may help you.

Make sure to discuss your other medical conditions, and all other medications you may be taking to manage those problems, including supplements.