Prozac (fluoxetine) is a brand-name prescription medication. The Food and Drug Administration (FDA) has approved it to treat the following conditions in adults:

In addition, Prozac can also be used in combination with olanzapine (Zyprexa) to treat the following conditions in adults:

Prozac can also be used in certain children with MDD, OCD, or in combination with olanzapine for depression related to bipolar disorder.

Here are some fast facts about Prozac:

In most cases, if Prozac works for you, your doctor will recommend taking it long-term. However, in some cases, your doctor may recommend short-term treatment. Before you start Prozac, your doctor will discuss your treatment plan with you.

As with other drugs, Prozac can cause side effects. Read on to learn about potential common, mild, and serious side effects. For a general overview of Prozac, including details about its uses, see this article.

Prozac can cause certain side effects, some of which are more common than others. These side effects may be temporary, lasting a few days to weeks. However, if the side effects last longer than that, bother you, or become severe, be sure to talk with your doctor or pharmacist.

These are just a few of the more common side effects reported by people who took Prozac in clinical trials:

* For more information about this side effect, see “Side effect specifics” below.

Mild side effects can occur with Prozac use. This list doesn’t include all possible mild side effects of the drug. For more information, you can refer to Prozac’s prescribing information.

Mild side effects that have been reported with Prozac include:

These side effects may be temporary, lasting a few days to weeks. However, if the side effects last longer than that, bother you, or become severe, be sure to talk with your doctor or pharmacist.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks side effects of the medication. If you develop a side effect while taking Prozac and want to tell the FDA about it, visit MedWatch.

* For more information about this side effect, see “Side effect specifics” below.

Prozac may cause serious side effects. The list below may not include all possible serious side effects of the drug. For more information, you can refer to Prozac’s prescribing information.

If you develop serious side effects while taking Prozac, call your doctor right away. If the side effects seem life threatening or you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Serious side effects that have been reported and their symptoms include:

* Prozac has a boxed warning for this side effect. This is a serious warning from the Food and Drug Administration (FDA). To learn more, see the “Side effect specifics” section below.
†An allergic reaction is possible after using Prozac. However, it’s not clear whether this side effect occurred in clinical trials. To learn more, see the “Side effect specifics” section below.

Prozac is approved to treat certain children and adults. However, the drug has a boxed warning for the risk of for the risk of suicidal thoughts and behaviors in certain people. Boxed warnings are the most serious warnings recommended by the FDA. The purpose of a boxed warning is to make patients and doctors aware of the risk of taking a medication.

Specifically, Prozac may increase the risk of suicidal thoughts and behaviors in children or young adults taking the drug. For more information on this warning, see the “Side effects specifics” section below.

Prozac is approved to treat the following conditions in children:

In most cases, children taking Prozac reported the same side effects that adults taking the drug experienced. Prozac side effects in teens were also usually the same as the side effects in adults. However, children taking Prozac may experience other side effects, such as feeling thirsty, muscle spasms, or urinary frequency.

In addition, it’s not known if the drug may have long-term effects on the growth or development of children. So, doctors may monitor your child’s height and weight to be sure that they’re growing as they should be while taking Prozac.

If you have concerns about side effects that your child may experience from taking Prozac, talk with their doctor.

You shouldn’t experience weight gain from taking Prozac. Weight gain wasn’t reported in clinical trials of people taking this drug.

In fact, weight loss was actually a side effect of this medication in clinical trials. This may be because Prozac can cause a decrease in appetite, which may lead to weight loss.

However, it’s possible for depression to cause weight gain to occur. Prozac can be used to treat depression.

So, if you notice weight gain during your treatment with Prozac, talk with your doctor. They can help you determine what may be causing the weight gain to occur. In addition, they may be able to recommend ways to help manage your weight.

Often, females* and males* taking Prozac will experience similar side effects. However, it’s possible for sexual side effects to occur from taking Prozac. Sexual side effects may differ between females and males.

For example, in males, Prozac may cause a decreased libido, erectile dysfunction, or a delay or trouble ejaculating. However, in females, this drug may decrease libido or cause a delay in orgasm.

For more information on sexual side effects that Prozac may cause, see the “Side effect details” section below.

* Sex and gender exist on spectrums. Use of the terms “female” and “male” in this article refers to sex assigned at birth.

Prozac may cause several side effects. Here are some frequently asked questions about the drug’s side effects and their answers.

Does stopping Prozac treatment cause withdrawal symptoms?

Yes, it’s possible that stopping treatment with Prozac may cause withdrawal symptoms to occur. Withdrawal symptoms are symptoms that can happen when your body is used to taking a medication that you suddenly stop taking.

Some examples of withdrawal symptoms that may occur from stopping Prozac include:

Because of these side effects, be sure to talk with your doctor before stopping treatment with Prozac. They’ll likely recommend slowly decreasing your dose of Prozac so that your body can adjust to the change.

If you’re interested in stopping treatment with Prozac, talk with your doctor about the safest way to do so.

What are the long-term side effects of Prozac?

Although uncommon, it’s possible for Prozac to cause long-term side effects to occur. Examples of long-term side effects that Prozac may cause include glaucoma, seizures, or hair loss.

If you’re concerned about long-term side effects from Prozac, talk with your doctor or pharmacist. They can discuss the risk of side effects with you and ways to help prevent side effects from occurring.

Are there side effects with a low dose of Prozac?

Yes, it’s possible to experience side effects if you take a low dose of Prozac. This drug is available in 10 milligram (mg), 20 mg, or 40 mg capsules. Taking even a low dose of Prozac may cause side effects to occur.

The lowest dose of Prozac that your doctor may prescribe for you is 10 mg. And, although higher doses of Prozac may have a higher risk of side effects, you still may experience side effects from lower doses.

If you’re concerned about side effects that you may experience from Prozac, talk with your doctor or pharmacist. They may be able to help recommend ways to reduce side effects that you experience. For example, if you’re concerned about Prozac 20 mg side effects, your doctor or pharmacist may be able to recommend ways to reduce side effects from occurring.

Prozac doesn’t have a high risk for misuse. Misuse of a drug means using it in a way that’s different than how the drug was prescribed to you. Misusing a drug may increase your risk of serious side effects and overdose.

However, even though Prozac isn’t commonly misused, stopping the drug suddenly may cause withdrawal symptoms. Withdrawal symptoms can happen if your body is used to a medication that you suddenly stop taking.

To learn more about withdrawal symptoms that may occur from Prozac, see the “FAQs about the side effects of Prozac” section above.

Learn more about some of the side effects that Prozac may cause. To find out how often side effects occurred in clinical trials, see the prescribing information for Prozac.

Increased risk of suicidal thoughts and behaviors

It’s possible for Prozac to increase the risk of suicidal thoughts and behaviors in certain people. In fact, Prozac has a boxed warning for this risk. A boxed warning is the most serious warning recommended by the FDA. The purpose of a boxed warning is to alert doctors and patients about the risks of taking a medication.

Antidepressants, including Prozac, have a boxed warning for the risk of suicidal thoughts and behaviors. This risk was seen in children and young adults ages 24 and younger taking the drug. The risk of this side effect is highest when you first start taking Prozac or when your dose of medication is increased.

It’s important to note that this risk was seen in people taking Prozac short-term. So, it’s not known if taking this drug long-term may still have this risk.

What you can do

Because of the risk of suicidal thoughts and behaviors, your doctor will likely recommend monitoring you throughout your treatment with Prozac. They may monitor you for increasing symptoms of depression, changes in behavior, or suicidal thoughts or behaviors. If you develop these symptoms, your doctor may recommend stopping Prozac and trying a different medication.

In addition, be sure to report any changes in mood to your doctor right away. Your doctor may also recommend that your family or loved ones watch for changes in behavior that may indicate worsening depression or suicidal thoughts or behaviors.

Sexual side effects

It’s possible for selective serotonin reuptake inhibitors (SSRIs), including Prozac, to cause sexual side effects. In fact, sexual side effects from Prozac were commonly reported in clinical trials of people taking the drug.

Examples of sexual side effects can include:

What you can do

If you notice sexual side effects during your treatment with Prozac, talk with your doctor. They may be able to recommend ways to manage sexual side effects that you experience. For example, your doctor may recommend Viagra (sildenafil) to treat erectile dysfunction that you experience from Prozac treatment.

Headache

You may experience headaches from taking Prozac. Although headaches weren’t one of the most common side effects in clinical trials of Prozac, they may occur.

What you can do

Tell your doctor if you’re experiencing headaches during your treatment with Prozac. Although rare, it’s possible for headaches to be due to other side effects of Prozac, including low blood sodium levels or serotonin syndrome. Your doctor will be able to help you determine what’s causing your headaches to occur.

In some cases, your doctor may recommend taking an over-the-counter medication, such as Tylenol (acetaminophen) to treat your headaches. If you’re experiencing headaches during your treatment with Prozac, talk with your doctor.

Nausea

You may experience nausea from taking Prozac. In fact, nausea was one of the most common side effects reported in clinical trials of Prozac.

What you can do

If you experience nausea from taking Prozac, talk with your doctor or pharmacist. They may be able to recommend ways to decrease this side effect from occurring. For example, in some cases, taking a medication with food may decrease nausea that you experience.

Hair loss

It’s possible to have hair loss from taking Prozac. Although hair loss wasn’t a common side effect reported in clinical trials, it can occur.

What you can do

If you notice hair loss during your treatment with Prozac, talk with your doctor or pharmacist. They may be able to recommend ways to reduce this side effect from occurring. For example, they may recommend using an over-the-counter medication, such as Rogaine (minoxidil) to manage hair loss.

Allergic reaction

As with most drugs, Prozac can cause an allergic reaction in some people. However, it’s not clear whether this side effect occurred in clinical trials.

Symptoms can be mild or serious and can include:

  • skin rash
  • itching
  • flushing
  • swelling under your skin, typically in your eyelids, lips, hands, or feet
  • swelling of your mouth, tongue, or throat, which can make it hard to breathe

What you can do

For mild symptoms of an allergic reaction, call your doctor right away. They may recommend ways to ease your symptoms and determine whether you should keep taking Prozac. However, if your symptoms are serious and you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Suicide prevention

If you know someone at immediate risk of self-harm, suicide, or hurting another person:

  • Ask the tough question: “Are you considering suicide?”
  • Listen to the person without judgment.
  • Call 911 or the local emergency number, or text TALK to 741741 to communicate with a trained crisis counselor.
  • Stay with the person until professional help arrives.
  • Try to remove any weapons, medications, or other potentially harmful objects.

If you or someone you know is having thoughts of suicide, a prevention hotline can help. The 988 Suicide and Crisis Lifeline is available 24 hours a day at 988. During a crisis, people who are hard of hearing can use their preferred relay service or dial 711 then 988.

Click here for more links and local resources.

Before you start treatment with Prozac, be sure to tell your doctor about any medical conditions that you have. They can help determine if Prozac is safe for you.

Boxed warning: Increased risk of suicidal thoughts and behaviors

This drug has a boxed warning for increased risk of suicidal thoughts and behaviors. This is a serious warning from the Food and Drug Administration (FDA). For details, see the “Side effect specifics” section above.

Other precautions

Be sure to talk with your doctor about your health history before you take Prozac. This drug may not be the right treatment for you if you have certain medical conditions or other factors that affect your health. These are considered drug-condition or drug-factor interactions. The conditions and factors to consider include:

Mood conditions. If you have any mood problems, such as bipolar disorder, tell your doctor before taking Prozac. In some cases, it’s possible for Prozac to increase the risk of manic episodes occurring in people with certain mood conditions. If you have a mood condition, your doctor can help determine whether Prozac is safe for you.

Seizures. If you have seizures, tell your doctor before taking Prozac. It’s possible for Prozac to increase your risk of seizures occurring. And, if you already have a seizure disorder, taking Prozac may raise your risk of having a seizure. If you have a seizure condition, your doctor can advise you on whether it’s safe for you to take Prozac.

Glaucoma. It’s possible for Prozac to increase the pressure in your eye, which can make glaucoma worse. So, if you have glaucoma, talk with your doctor to see whether Prozac is safe for you.

Heart conditions. If you have any heart problems, such as an arrhythmia, tell your doctor before taking Prozac. This medication can increase your risk of heart rhythm changes occurring. And, if you already have a heart condition, taking Prozac may make your condition worse. In this case, your doctor can help determine whether Prozac may be safe for you.

Bleeding conditions. Prozac may increase your risk of bleeding. If you have a bleeding condition, taking Prozac may make it even easier for you to bleed. Tell your doctor about any bleeding conditions that you have before taking Prozac.

Allergic reaction. If you’ve had an allergic reaction to Prozac or any of its ingredients, your doctor will likely not prescribe Prozac. Ask your doctor what other medications may be better options for you.

Liver problems. Prozac is removed from your body by your liver. If your liver isn’t functioning properly, it’s possible for Prozac to build up in your body. This can increase your risk of side effects from the drug. Talk with your doctor if you have liver problems before starting treatment. They may recommend a lower dose of Prozac for you.

Low electrolyte levels. Prozac may decrease sodium (salt) levels in your blood. If you have an electrolyte condition such as low blood sodium levels, taking Prozac may increase your risk of side effects. In addition, Prozac may increase your risk of developing a heart side effect such as increased heart rate if you have an electrolyte condition.

If you have low electrolyte levels talk with your doctor before starting treatment with Prozac. They’ll likely recommend managing your electrolyte levels before starting Prozac.

Older adults. It’s possible that older adults (age 65 years or older) taking Prozac may be at an increased risk of side effects, such as low blood sodium levels. If you’re an older adult, your doctor may monitor you more often for side effects while you’re taking Prozac.

Electroconvulsive therapy. It’s possible that if you receive electroconvulsive therapy (ECT) for treatment-resistant depression, you may be at an increased risk of seizures from taking Prozac. So, if you receive ECT, talk with your doctor to see whether it’s safe for you to take Prozac.

Diabetes. If you have diabetes, taking Prozac can cause changes in your blood sugar to occur. This may make your diabetes worse and can increase your risk of developing low blood sugar. Due to this risk, if you have diabetes, your doctor may recommend more frequent monitoring of your blood sugar while you’re taking Prozac.

Alcohol with Prozac

There aren’t any known interactions between Prozac and alcohol.

However, drinking alcohol while you’re taking Prozac may increase your risk of side effects from the drug. For example, both Prozac and alcohol may cause:

  • nausea
  • headache
  • dizziness
  • sleepiness

Talk with your doctor to see if it’s safe for you to drink alcohol while taking Prozac.

Pregnancy and breastfeeding while taking Prozac

It may not be safe to take Prozac during pregnancy or while breastfeeding.

Selective serotonin reuptake inhibitors (SSRIs), including Prozac, may increase the risk of certain developmental problems. These can include difficulty breathing, trouble feeding, or irritability. In addition, the drug may increase the risk of pulmonary hypertension (high pressure in the lungs) in a newborn.

At this time, it’s not known if Prozac may increase the risk of congenital anomalies (commonly known as birth defects). There’s currently a pregnancy registry for antidepressant drugs, such as Prozac. The purpose of a pregnancy registry is to collect information on the risks of taking a drug during pregnancy. You can sign up for the registry online or by calling 844-405-6185.

In addition, it’s important to note that untreated depression may also have effects on a developing fetus. So, if you’re pregnant or planning to become pregnant, talk with your doctor before taking Prozac. They can help determine what the best treatment plan is for you.

Prozac can pass into breast milk, so a breastfeeding baby can be exposed to the drug. Babies exposed to Prozac may experience side effects such as agitation, irritability, and trouble feeding.

If you’d like to breastfeed while taking Prozac, talk with your doctor. They can help determine if breastfeeding may be safe for your baby.

Side effects with Prozac may occur, but they’re usually mild. However, it’s also possible for this drug to cause serious side effects.

If you’d like to learn more about Prozac, talk with your doctor or pharmacist. They can help answer any questions you have about side effects from taking the drug.

Besides talking with your doctor, you can do some research on your own. These articles might help:

  • More information about Prozac. For details about other aspects of Prozac, refer to this article.
  • Drug comparison. Learn how Prozac compares with Zoloft and Lexapro.
  • A look at your condition. For details about your condition, see our mental health hub.

Disclaimer: Medical News Today has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.