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Disclaimer: This is not meant to be medical advice, and always discuss with your care manager, prescriber or other doctor before making any medication changes or taking action, unless otherwise indicated. Please refer to the package insert included with your medication.

What is Fluoxetine (Prozac®)?

Fluoxetine, which is the generic name for Prozac®, is a type of medication known as an SSRI (selective serotonin reuptake inhibitor) and one of the most commonly prescribed medications to treat depression and anxiety disorders. Fluoxetine was the first SSRI approved by the FDA. Fluoxetine’s approval for the treatment of depression was an important moment because of the significant benefits offered by SSRIs with few side effects. By blocking the reuptake of serotonin by neurons, Fluoxetine increases the available serotonin in the brain for neurotransmission. 

How does Fluoxetine (Prozac®) work?

SSRIs like Fluoxetine treat depression and anxiety by increasing levels of serotonin in the brain. They do this by preventing the reuptake of serotonin by neurons, leaving more serotonin available to act on receptors - hence the name serotonin reuptake inhibitors. Fluoxetine is also thought to have an effect on norepinephrine and dopamine neurotransmission through its effects on a specific type of serotonin receptor, the 5HT2C receptor. Exactly how this results in improved mood is likely more complicated, but the positive effects on mood and anxiety have been shown in numerous scientific studies.

How long does it take Fluoxetine (Prozac®) to work?

Improvement in anxiety often takes place within 1 week of starting a reasonable dose. Mood benefits, such as no longer feeling depressed or feeling happier, may take longer (2 to 4 weeks). If you don’t experience improvement at higher doses, this medication may not work for you. However, if you have not improved at lower doses, it may be that the dose is just too low. Finding the right dose of a medication sometimes takes time, but your provider will help guide you through the process by closely following your symptoms and adjusting treatment as necessary.

How do I take Fluoxetine (Prozac®)?

Always take Fluoxetine as prescribed. You can take Fluoxetine in the morning or at night. Most people take it in the morning. The most important thing is to pick a time when you are most likely to be consistent. 

You can take Fluoxetine with or without food. Taking it with food reduces the most common side effects of Fluoxetine, a mild stomach upset or nausea. This nearly always goes away with time. You will likely not need to do this forever, but it is helpful when you are starting or when you are increasing the dose. 

What if I miss a dose of Fluoxetine (Prozac®)? 

If it is almost time for your next dose, skip the missed dose and go back to taking at your normal time. Do not take 2 doses at the same time or extra doses. If you find yourself consistently missing your medication, let your Mantra-affiliated prescriber know. 

Can I take Fluoxetine (Prozac®) while drinking?

All SSRIs, including Fluoxetine, can increase your sensitivity towards alcohol. The most conservative psychiatrists will tell you that it makes 1 drink feel like 2. Patients often note that when they drink, they feel much more intoxicated than they usually do. This can even lead to a blackout. Please be careful when drinking alcohol on SSRIs. 

Will I gain weight on Fluoxetine (Prozac®)?

When you follow the average American over 6 months in drug studies, you see weight gain in both the placebo and the medication groups. Thus, it is hard to know if weight gain, even with excellent data, is a true medication side effect or the result of recovery from depression and the reversal of undesired weight loss. However, clinical experience shows that some people may experience a modest amount of weight gain on SSRIs. There is also likely a very small group of people who gain significant weight (20 pounds or more) on SSRIs. Please monitor and tell your Mantra-affiliated prescriber if you experience weight gain so that you can make a plan together.

Important Safety Information

All medications have risks. While most of the side effects from Fluoxetine are either mild or very rare, you should discuss the risks and benefits of the medication. If you experience any side effects, please notify your provider immediately. If you have a serious side effect, contact your in-person health care provider immediately. If you are having an emergency, call 911 or go to your nearest emergency room.

Read the Medication Guide that comes with fluoxetine before you start taking it and each time you get a refill. There may be new information. This Medication Guide does not take the place of talking to your healthcare provider about your medical condition or treatment. Talk with your healthcare provider if there is something you do not understand or want to learn more about.

What is the most important information I should know about fluoxetine?

Fluoxetine and other antidepressant medicines may cause serious side effects, including:

1. Suicidal thoughts or actions:

  • Fluoxetine and other antidepressant medicines may increase suicidal thoughts or actions in some children, teenagers, or young adults within the first few months of treatment or when the dose is changed.
  • Depression or other serious mental illnesses are the most important causes of suicidal thoughts or actions. •
  • Watch for these changes and call your healthcare provider right away if you notice:
    − New or sudden changes in mood, behavior, actions, thoughts, or feelings, especially if severe.
    − Pay particular attention to such changes when fluoxetine is started or when the dose is changed.

Keep all follow-up visits with your healthcare provider and call between visits if you are worried about symptoms.

Call your healthcare provider right away if you have any of the following symptoms, or call 911 if an emergency, especially if they are new, worse, or worry you:

  • attempts to commit suicide
  • acting on dangerous impulses
  • acting aggressive or violent
  • thoughts about suicide or dying
  • new or worse depression
  • new or worse anxiety or panic attacks
  • feeling agitated, restless, angry or irritable
  • trouble sleeping
  • an increase in activity or talking more than what is normal for you
  • other unusual changes in behavior or mood

Call your healthcare provider right away if you have any of the following symptoms, or call 911 if an emergency. Fluoxetine may be associated with these serious side effects:

2. Serotonin Syndrome. This condition can be life-threatening and may include:

  • agitation, hallucinations, coma or other changes in mental status
  • coordination problems or muscle twitching (overactive reflexes)
  • racing heartbeat, high or low blood pressure
  • sweating or fever
  • nausea, vomiting, or diarrhea
  • muscle rigidity

3. Severe allergic reactions:

  • trouble breathing
  • swelling of the face, tongue, eyes or mouth
  • rash, itchy welts (hives) or blisters, alone or with fever or joint pain

4. Abnormal bleeding: Fluoxetine and other antidepressant medicines may increase your risk of bleeding or bruising, especially if you take the blood thinner warfarin (Coumadin®, Jantoven®), a non-steroidal anti-inflammatory drug (NSAIDs, like ibuprofen or naproxen), or aspirin.

5. Seizures or convulsions

6. Manic episodes:

  • greatly increased energy
  • severe trouble sleeping
  • racing thoughts
  • reckless behavior
  • unusually grand ideas
  • excessive happiness or irritability
  • talking more or faster than usual

7. Changes in appetite or weight. Children and adolescents should have height and weight monitored during treatment.

8. Low salt (sodium) levels in the blood. Elderly people may be at greater risk for this. Symptoms may include:

  • headache
  • weakness or feeling unsteady
  • confusion, problems concentrating or thinking or memory problems

9. Visual problems

  • eye pain
  • changes in vision
  • swelling or redness in or around the eye
    Only some people are at risk for these problems. You may want to undergo an eye examination to see if you are at risk and receive preventative treatment if you are.

Do not stop fluoxetine without first talking to your healthcare provider. Stopping Lexapro too quickly may cause serious symptoms including:

  • anxiety, irritability, high or low mood, feeling restless or changes in sleep habits
  • headache, sweating, nausea, dizziness
  • electric shock-like sensations, shaking, confusion

What is fluoxetine?

Fluoxetine is a prescription medicine used to treat depression. It is important to talk with your healthcare provider about the risks of treating depression and also the risks of not treating it. You should discuss all treatment choices with your healthcare provider.

Fluoxetine is used to treat:

  • Major Depressive Disorder (MDD)
  • Obsessive Compulsive Disorder (OCD)
  • Bulimia Nervosa*
  • Panic Disorder*
  • Depressive episodes associated with Bipolar I Disorder, taken with olanzapine (Zyprexa)*
  • Treatment Resistant Depression (depression that has not gotten better with at least 2 other treatments), taken with olanzapine (Zyprexa)*
    *Not approved for use in children.

Talk to your healthcare provider if you do not think that your condition is getting better with fluoxetine treatment.

Who should not take fluoxetine?

Do not take fluoxetine if you:

  • are allergic to fluoxetine hydrochloride or any of the ingredients in fluoxetine. See the end of this Medication Guide for a complete list of ingredients in fluoxetine.
  • take a Monoamine Oxidase Inhibitor (MAOI). Ask your healthcare provider or pharmacist if you are not sure if you take an MAOI.
    − Do not take an MAOI within 5 weeks of stopping fluoxetine.
    − Do not start fluoxetine if you stopped taking an MAOI in the last 2 weeks.
    People who take fluoxetine close in time to an MAOI may have serious or even lifep-threatening side effects. Get medical help right away if you have any of these symptoms:
    − high fever
    − uncontrolled muscle spasms
    − stiff muscles
    − rapid changes in heart rate or blood pressure
    − confusion
    − loss of consciousness (pass out)
  • take Mellaril® (thioridazine). Do not take Mellaril® within 5 weeks of stopping fluoxetine because this can cause serious heart rhythm problems or sudden death.
  • take the antipsychotic medicine pimozide (Orap®) because this can cause serious heart problems.

What should I tell my healthcare provider before taking fluoxetine?

Ask if you are not sure.

Before starting fluoxetine, tell your healthcare provider if you:

  • are taking certain drugs or treatments such as:
    − Triptans used to treat migraine headache
    − Medicines used to treat mood, anxiety, psychotic or thought disorders, including tricyclics, lithium, SSRIs, SNRIs, MAOIs (including linezolid, an antibiotic), or antipsychotics
    − Tramadol
    − Over-the-counter supplements such as tryptophan or St. John’s Wort
    − Electroconvulsive therapy (ECT)
  • have liver problems
  • have kidney problems
  • have heart problems
  • have or had seizures or convulsions
  • have bipolar disorder or mania
  • have low sodium levels in your blood
  • have a history of a stroke
  • have high blood pressure
  • have or had bleeding problems
  • are pregnant or plan to become pregnant. It is not known if fluoxetine will harm your unborn baby. Talk to your healthcare provider about the benefits and risks of treating depression during pregnancy.
  • are breast-feeding or plan to breast-feed. Some fluoxetine may pass into your breast milk. Talk to your healthcare provider about the best way to feed your baby while taking fluoxetine.

Tell your healthcare provider about all the medicines that you take, including prescription and non-prescription medicines, vitamins, and herbal supplements. Fluoxetine and some medicines may interact with each other, may not work as well, or may cause serious side effects.

Your healthcare provider or pharmacist can tell you if it is safe to take fluoxetine with your other medicines. Do not start or stop any medicine while taking fluoxetine without talking to your healthcare provider first.

If you take fluoxetine, you should not take any other medicines that contain fluoxetine hydrochloride including:

  • Symbyax® (olanzapine and fluoxetine hydrochloride)
  • Sarafem® (fluoxetine)
  • Prozac®
  • Prozac® Weekly™

How should I take fluoxetine?

  • Take fluoxetine exactly as prescribed. Your healthcare provider may need to change the dose of fluoxetine until it is the right dose for you. Each tablet can be broken in half (along the functional score).
  • Fluoxetine may be taken with or without food.
  • If you miss a dose of fluoxetine, take the missed dose as soon as you remember. If it is almost time for the next dose, skip the missed dose and take your next dose at the regular time. Do not take two doses of fluoxetine at the same time.
  • If you take too much fluoxetine, call your healthcare provider or poison control center right away, or get emergency treatment.

What should I avoid while taking fluoxetine?

Fluoxetine can cause sleepiness or may affect your ability to make decisions, think clearly, or react quickly. You should not drive, operate heavy machinery, or do other dangerous activities until you know how fluoxetine affects you. Do not drink alcohol while using fluoxetine.

What are the possible side effects of fluoxetine?

Fluoxetine may cause serious side effects, including:

  • See “What is the most important information I should know about fluoxetine?”
  • Problems with blood sugar control. People who have diabetes and take fluoxetine may have problems with low blood sugar while taking fluoxetine. High blood sugar can happen when fluoxetine is stopped. Your healthcare provider may need to change the dose of your diabetes medicines when you start or stop taking fluoxetine.
  • Feeling anxious or trouble sleeping

Common possible side effects in people who take fluoxetine include:

  • unusual dreams
  • sexual problems
  • loss of appetite, diarrhea, indigestion, nausea or vomiting, weakness, or dry mouth
  • flu symptoms
  • feeling tired or fatigued
  • change in sleep habits
  • yawning
  • sinus infection or sore throat
  • tremor or shaking
  • sweating
  • feeling anxious or nervous
  • hot flashes
  • rash

Other side effects in children and adolescents include:

  • increased thirst
  • abnormal increase in muscle movement or agitation
  • nose bleed
  • urinating more often
  • heavy menstrual periods
  • possible slowed growth rate and weight change. Your child’s height and weight should be monitored during treatment with fluoxetine.

Tell your healthcare provider if you have any side effect that bothers you or that does not go away. These are not all the possible side effects of fluoxetine. For more information, ask your healthcare provider or pharmacist.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

How should I store fluoxetine?

  • Store fluoxetine at room temperature between 68 °F and 77 °F (20 °C to 25 °C).
  • Keep fluoxetine away from light.
  • Keep fluoxetine bottle closed tightly.

Keep fluoxetine and all medicines out of the reach of children.

General information about fluoxetine

Medicines are sometimes prescribed for purposes other than those listed in a Medication Guide. Do not use fluoxetine for a condition for which it was not prescribed. Do not give fluoxetine to other people, even if they have the same condition. It may harm them.

This Medication Guide summarizes the most important information about fluoxetine. If you would like more information, talk with your healthcare provider. You may ask your healthcare provider or pharmacist for information about fluoxetine that is written for healthcare professionals.

For more information about fluoxetine call 1-888-594-4332.

What are the ingredients in fluoxetine tablets, 60 mg?

Active ingredient: fluoxetine hydrochloride

Inactive ingredients: mannitol, microcrystalline cellulose, maize starch, povidone, hypromellose, magnesium stearate, titanium dioxide, sucrose, glycerol, and polysorbate.

Tell your healthcare providers

Telemedicine does not replace your primary care physician. It is important to keep your primary care physician, other healthcare providers, and pharmacist informed of all medications you are taking, including those prescribed by your Mantra-affiliated provider, as they can interact with other medicines you may be taking.

Additional Resources

FDA Guide: Fluoxetine

FDA Access Data: Fluoxetine

Medline Plus: Fluoxetine