Prozac (fluoxetine) is a prescription drug that’s used to treat certain mental health conditions, including depression. The drug comes as a capsule that you swallow. It’s usually taken once per day in the morning.
Prozac is prescribed to adults to treat:
- panic disorder
- obsessive-compulsive disorder (OCD)
- depression
- depression related to bipolar I disorder*
- treatment-resistant depression*
- bulimia nervosa (an eating disorder)
Prozac is also prescribed to some children to treat:
- OCD
- depression
- depression related to bipolar I disorder*
The active ingredient in Prozac is fluoxetine. (An active ingredient is what makes a drug work.) Prozac belongs to a group of drugs called selective serotonin reuptake inhibitors (SSRIs).
This article describes the dosages of Prozac, as well as its strengths and how to take it. To learn more about Prozac, see this in-depth article.
* For this condition, Prozac is used together with olanzapine (Zyprexa).
This section covers standard dosage information for Prozac. Before prescribing this medication, your doctor will talk with you about the dosage instructions specific to your condition.
Note: This chart highlights the basics of Prozac’s dosages for adults. (For details about children’s dosages, see the “What’s the dosage of Prozac for children?” section below.) Prozac’s strengths are in milligrams (mg). Be sure to read on for more detail.
| Condition | Starting dosage | Maximum dosage |
| panic disorder | 10 mg per day | 60 mg per day |
| obsessive-compulsive disorder (OCD) | 20 mg per day | 80 mg per day |
| depression | 20 mg per day | 80 mg per day |
| treatment-resistant depression* | 20 mg per day | 50 mg per day |
| depression related to bipolar I disorder* | 20 mg per day | 50 mg per day |
| bulimia nervosa (an eating disorder) | 60 mg per day† | 60 mg per day |
* For this condition, Prozac is used together with olanzapine (Zyprexa).
† For this condition, doctors may prescribe a lower dose to start. Then they’ll increase it over several days to the recommended dose of 60 mg.
What is the form of Prozac?
Prozac comes as a capsule that you swallow.
What strengths does Prozac come in?
Prozac capsules come in the following strengths:
- 10 mg
- 20 mg
- 40 mg
What are the usual dosages of Prozac?
Your doctor will likely start by prescribing a low dosage of Prozac. They may adjust it over time to reach the right therapeutic dose for you. (A therapeutic dose is a dose that treats your condition and manages your symptoms.) They’ll ultimately prescribe the smallest dosage that provides the desired effect.
The information below describes dosages that are commonly recommended for adults. But be sure to take the dosage your doctor prescribes for you. They’ll determine the best dosage to fit your needs.
Dosage for panic disorder
For panic disorder (a kind of anxiety disorder), your doctor may initially prescribe a low dose of Prozac. The starting dosage is 10 mg per day.
After 1 week, your doctor may increase your dosage to 20 mg per day. This is the recommended dosage for panic disorder. They may increase it further to reach the dose that’s right for you.
The usual daily dose ranges from 10 mg to 60 mg. The maximum recommended dosage for panic disorder is 60 mg.
Dosage for OCD
For OCD in adults, the recommended starting dosage is 20 mg per day. Your doctor may gradually increase your dosage to reach the dose that’s right for you.
The usual daily dose ranges from 20 mg to 60 mg. The maximum recommended dosage for OCD is 80 mg per day.
Dosage for depression related to bipolar I disorder
For depression related to bipolar I disorder, Prozac’s recommended starting dosage in adults is 20 mg per day. Your doctor may gradually increase or adjust your dosage to reach the dose that’s right for you.
Prozac’s usual daily dose ranges from 20 mg to 50 mg. The maximum recommended dosage is 50 mg.
For this use, Prozac is prescribed together with olanzapine (Zyprexa). Your doctor will recommend the dosage of olanzapine that’s right for you.
Dosage for depression
For depression in adults, the typical dosage of Prozac is 20 mg per day. You’ll likely take this dosage for the first several weeks or longer. Then your doctor may increase or adjust your dosage over time to reach the dose that’s right for you.
The usual daily dose ranges from 20 mg to 80 mg. The maximum recommended dosage is 80 mg per day.
Dosage for treatment-resistant depression
For treatment-resistant depression in adults, the usual starting dosage is 20 mg per day. You’ll likely take this dosage for the first several weeks or longer. Then your doctor may increase or adjust your dosage over time to reach the dose that’s right for you.
The usual daily dose ranges from 20 mg to 50 mg. The maximum recommended dosage is 50 mg per day.
For this use, Prozac is prescribed together with olanzapine (Zyprexa). Your doctor will recommend the dosage of olanzapine that’s right for you.
Dosage for bulimia nervosa
For bulimia nervosa, the usual dosage of Prozac is 60 mg per day. Doctors sometimes prescribe a lower dose to start. Then they’ll increase it over several days until they reach the recommended dose.
For this use, 60 mg per day is the recommended dosage and the maximum dosage of Prozac.
What’s the dosage of Prozac for children?
Prozac is approved to treat:
- depression in children ages 8 years and older
- OCD in children ages 7 years and older
- depression related to bipolar I disorder in children ages 10 years and older
The chart below summarizes the usual recommended dosages of Prozac for children. Prozac’s strengths are in milligrams (mg).
| Condition | Starting dosage | Maximum dosage |
| depression | 10 mg per day to 20 mg per day | 20 mg per day |
| OCD | 10 mg per day | 60 mg per day |
| depression related to bipolar I disorder* | 20 mg per day | 50 mg per day |
* For this condition, Prozac is used together with olanzapine (Zyprexa).
Dosage for depression
For depression in children, Prozac’s usual starting dosage is 10 mg per day to 20 mg per day. Your child’s doctor may start by prescribing 10 mg per day and increase it to 20 mg per day after 1 week.
Your child’s dosage may need to be adjusted based on their body weight. Their doctor will determine the dosage that’s right for your child. For details, see the “Dosage adjustments” section below.
Dosage for OCD
For OCD in children, the usual starting dosage is 10 mg per day. After 2 weeks, your child’s doctor will likely increase their dosage to 20 mg per day. They may raise the dosage over time until they reach the dose that’s right for your child.
The recommended daily dose ranges from 20 mg to 60 mg.
Dosage for depression related to bipolar I disorder
For depression related to bipolar I disorder, Prozac’s recommended starting dosage is 20 mg per day. Your child’s doctor may gradually increase their dosage over time until they reach the dose that’s right for your child.
The maximum dosage of Prozac for this use in children is 50 mg per day.
For depression related to bipolar I disorder, Prozac is prescribed together with olanzapine (Zyprexa). Your child’s doctor will recommend the dosage of olanzapine that’s right for your child.
Is Prozac used long term?
Yes, Prozac is usually taken as a long-term treatment. If you and your doctor determine that it’s safe and effective for your condition, you’ll likely take it long term.
Dosage adjustments
Your doctor may decrease your Prozac dosage if you have liver problems or you’re age 65 years or older.
The dosage of Prozac may also need to be adjusted for children with a low body weight. For example, if your child weighs less than usual for their age, their doctor may prescribe a lower dosage.
Below are answers to some commonly asked questions about Prozac’s dosage.
What is the maximum dose of Prozac I can take?
The recommended maximum dose of Prozac varies by age and the condition being treated. For details, see the “What factors can affect my dosage?” section below.
For example, the recommended maximum dosage for depression and obsessive-compulsive disorder (OCD) is 80 mg per day. But for bulimia nervosa (an eating disorder) and panic disorder, it is 60 mg per day. To learn more, see the “What is Prozac’s dosage?” section above.
Keep in mind that the response to a medication differs between people. This is why it’s important to take Prozac exactly as your doctor prescribes. For example, the maximum dose for you may be a lethal dose for someone else. Your doctor will recommend the right dosage for you.
Do not take more medication than your doctor prescribes. Doing so can increase your risk of serious side effects. (For details about Prozac’s side effects, you can read this article.)
If you have questions about the maximum dose of Prozac that you can take, talk with your doctor or pharmacist.
Can I avoid side effects such as weight loss if I take a low dose of Prozac?
It depends. Prozac side effects, which may include weight loss, can occur with any dose. The risk increases at higher doses. So the risk of side effects, such as weight loss, may decrease with a lower dosage of Prozac.
Always take the dosage of Prozac your doctor prescribes. They’ll prescribe the lowest dose of Prozac that relieves your symptoms and treats your condition. (For details about Prozac’s side effects, you can read this article.)
If you’re concerned about weight loss with Prozac, talk with your doctor. They may monitor your (or your child’s) weight during treatment with Prozac.
If my Prozac dose increases from 10 mg to 20 mg, will I have a higher risk of side effects?
It’s possible. Prozac side effects can happen with any dose. But a dose increase may raise the risk or severity of side effects.
It’s important to note that Prozac has a
Be sure to always take Prozac exactly as your doctor prescribes. Do not change your dosage without your doctor’s recommendation. To review Prozac’s usual recommended dosages, see the “What is Prozac’s dosage?” section above.
If you have more questions about dosage changes and side effects, talk with your doctor. You can also read about Prozac’s side effects in this article.)
What’s the dosage of Prozac when it’s taken with olanzapine?
Olanzapine (Zyprexa) is prescribed together with Prozac for certain conditions. These include treatment-resistant depression in adults and depression associated with bipolar I disorder in adults and some children. For both conditions, the usual daily dose of Prozac in adults ranges from 20 mg to 50 mg. But always take the dosage that your doctor prescribes.
Olanzapine and fluoxetine (the active ingredient in Prozac) are also the active ingredients in the brand-name drug Symbyax. This drug is available as a generic version. Your doctor may prescribe you Symbyax instead of Prozac and olanzapine together. If your doctor prescribes Symbyax, they’ll recommend the right dosage for you.
If you miss a dose of Prozac, take it as soon as you remember. If it’s almost time for your next dose, skip the missed dose and take your next dose at the scheduled time. Do not take two doses together to make up for a missed dose.
If you need help remembering to take your dose of Prozac on time, try using a medication reminder. This can include setting an alarm or downloading a reminder app on your phone.
The dosage of Prozac you’re prescribed may depend on several factors. These include:
- the type and severity of the condition you’re taking the drug to treat
- your age
- body weight for children
- other conditions you may have (see the “Dosage adjustments” section above)
Prozac is usually taken once per day in the morning. In some cases, your doctor may recommend that you take Prozac twice per day. For example, if your dosage is 40 milligrams (mg) per day, your doctor may recommend taking 20 mg in the morning and 20 mg at noon.
If you take Prozac with olanzapine (Zyprexa), your doctor will likely recommend taking both drugs at night. (Prozac and olanzapine are prescribed together for depression related to bipolar I disorder and treatment-resistant depression. For details, see the “What is Prozac’s dosage?” section above.)
You can take Prozac with or without food.
For information on the expiration, storage, and disposal of Prozac, see this article.
Accessible drug containers and labels
If you find it hard to read the prescription label on your medication, tell your doctor or pharmacist. Some pharmacies provide medication labels that:
- have large print or use braille
- feature a code you can scan with a smartphone to change the text to audio
Your doctor or pharmacist may be able to recommend pharmacies that offer these accessibility features if your current pharmacy doesn’t.
If you have trouble opening medication bottles, let your pharmacist know. They may be able to supply Prozac in an easy-open container. They may also have tips to help make it simpler to open the drug’s container.
Prozac doesn’t have a high risk of misuse. Drug misuse means taking a drug in a way other than how a doctor prescribes it.
If you have questions about drug misuse and Prozac, talk with your doctor.
Do not take more Prozac than your doctor prescribes, as this can lead to serious side effects.
Symptoms of overdose
Symptoms caused by a Prozac overdose can include:
- dizziness
- increased blood pressure
- fainting
- slow, fast, or irregular heartbeat or heart rate
- hallucinations (seeing or hearing things that aren’t really there)
- confusion
- tremors (shakiness or shaky limbs)
- seizure
- coma
What to do in case you take too much Prozac
Call your doctor right away if you think you’ve taken too much Prozac. You can also call 800-222-1222 to reach America’s Poison Centers or use its online resource. But if you have severe symptoms, immediately call 911 (or your local emergency number) or go to the nearest emergency room.
You may have withdrawal symptoms if you stop taking Prozac suddenly. Withdrawal symptoms are side effects that can occur when you stop taking a drug that your body has become dependent on.
Prozac withdrawal symptoms can include:
- dizziness
- irritability
- agitation
- anxiety
- feeling of indifference or discontent
- electric shock sensations
- headache
- insomnia
- mood changes
If you and your doctor decide that you should stop taking Prozac, they’ll gradually decrease your dosage. This may help decrease the risk of withdrawal symptoms or their severity.
It’s important to follow your doctor’s instructions for stopping Prozac treatment. Your doctor will recommend a schedule that slowly reduces your dosage over time.
Tell your doctor if you have bothersome withdrawal symptoms while stopping Prozac treatment. They may have you temporarily go back to your previous dose or decrease your dosage more slowly.
Note that Prozac takes a while to get out of your system after your last dose. So if withdrawal symptoms occur, they may not start right away.
If you have questions about stopping your Prozac treatment or what side effects to expect, talk with your doctor.
The sections above describe the usual dosages provided by the drugmaker. If your doctor recommends Prozac for you, they’ll prescribe the dosage that’s right for you. To review Prozac’s usual recommended dosages, see the “What is Prozac’s dosage?” section above.
Remember, you should not change your dosage of Prozac without your doctor’s recommendation. Only take Prozac exactly as prescribed. Talk with your doctor if you have questions or concerns about your current dosage.
Here are some examples of questions you may want to ask your doctor:
- How long will I need to wait before any dose changes?
- Does my dosage of Prozac need to change if I’m taking other drugs along with it?
- Will you lower my dosage if I have side effects from Prozac?
- Will my dosage of Prozac need to change if I have kidney problems?
To learn more about Prozac, see these articles:
- Prozac (fluoxetine)
- Side Effects of Prozac: What You Need to Know
- Prozac Interactions: Alcohol, Medications, and Other Factors
To get information on different conditions and tips for improving your health, subscribe to any of Healthline’s newsletters. You may also want to check out the online communities at Bezzy. It’s a place where people with certain conditions can find support and connect with others.
Disclaimer: Healthline 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.
