Brain & Nervous System Treatment What to Know About Fluoxetine Antidepressant That Is a Generic Version of Prozac By Heidi Moawad, MD facebook linkedin Heidi Moawad is a neurologist and expert in the field of brain health and neurological disorders. Dr. Moawad regularly writes and edits health and career content for medical books and publications. Learn about our editorial process Heidi Moawad, MD Medically reviewed by Medically reviewed by Claudia Chaves, MD on September 18, 2020 Claudia Chaves, MD, is board-certified in cerebrovascular disease and neurology with a subspecialty certification in vascular neurology. She is an associate professor of neurology at Tufts Medical School and medical director of the Lahey Clinic Multiple Sclerosis Center in Lexington, Massachusetts. Learn about our Medical Review Board Claudia Chaves, MD Updated on October 13, 2020 Print Table of Contents View All Table of Contents Uses Before Taking Dosage Side Effects Warnings and Interactions Fluoxetine is a prescription antidepressant that is also used for treating several other psychiatric conditions in children and adults. This medication is taken by mouth and it is available in generic (fluoxetine) and brand (Prozac, Sarafem, Prozac Weekly) formulations. Fluoxetine is a selective serotonin reuptake inhibitor (SSRI) that prolongs the action of the neurotransmitter serotonin. This drug can be highly effective, but it is also associated with several serious adverse effects, such as suicidal thoughts, heart rhythm abnormalities, mania, serotonin syndrome, and more. SDI Productions / Getty Images Uses Fluoxetine is prescribed for the treatment of several psychiatric conditions. Generally, when this medication is prescribed, the treatment plan includes other methods of managing the diagnosed conditions, such as psychotherapy and lifestyle modification. Fluoxetine is approved for treating: Major depressive disorder: Adults and children age 8 and older Obsessive-compulsive disorder (OCD): Adults and children ages 7 and older Bulimia nervosa: Adults age 18 and older Panic disorder: Adults age 18 and older These conditions are associated with low serotonin levels or altered serotonin metabolism. Serotonin is a neurotransmitter that affects mood, anxiety, and a variety of functions. Normally a serotonin transporter (SERT) removes serotonin from nerve endings to modulate serotonin’s effects. Fluoxetine keeps serotonin active by inhibiting the reuptake of this neurotransmitter by SERT.2 The medication may also have other actions that play a role in its therapeutic effect. Fluoxetine keeps serotonin active by inhibiting the reuptake of this neurotransmitter by SERT. The medication may also have other actions that play a role in its therapeutic effect. Off-Label Uses Fluoxetine is sometimes used for conditions that it is not specifically FDA-approved for. These include a variety of mood, anxiety, sexual, and eating disorders. Before Taking Fluoxetine should be taken with caution and there are several contraindications. If you are pregnant or breastfeeding, you and your doctor need to consider the risks and benefits of taking this medication. And fluoxetine has not been established as safe for children under age eight who have depression or for children under age seven who have OCD. You should not take fluoxetine if it or another SSRI has ever caused you to have an allergic reaction, such as a rash or breathing difficulties. Precautions and Contraindications There are several conditions that can increase your risk of having an adverse effect of fluoxetine. Conditions that can be associated with adverse effects of fluoxetine include: Serotonin syndrome: If you have had serotonin syndrome in response to any medication in the past, it’s important to know that fluoxetine can trigger this condition. Symptoms of serotonin syndrome include agitation, confusion, diarrhea, and muscle rigidity.Suicidal ideation: There is an increased risk of suicidal ideation associated with fluoxetine, particularly in children, adolescents, and young adults.Cardiac arrhythmia: Fluoxetine can lead to irregular heart rhythms, and this is an especially high risk if you already have a predisposition to cardiac arrhythmias. This medication is specifically associated with long QT syndrome.Glaucoma: This medication can exacerbate certain types of glaucoma, especially if your glaucoma is untreated. Other SSRIs Fluoxetine is a generic medication. Prozac is a commonly prescribed brand of fluoxetine. Fluoxetine is available as a tablet, and Prozac is available as a tablet, an extended-release tablet, and as an oral solution. Other SSRIs include Zoloft (sertraline), Paxil (paroxetine), Lexapro (escitalopram), Celexa (citalopram), and others. Dosage Prozac is available in a variety of strengths and preparations, including 10mg, 20mg,40mg, and 60mg pills and as an oral solution. Below are fluoxetine manufacturers' recommended doses, although your doctor may start you on a lower dose and build up to a different target dose depending on your individual circumstances. Starting Doses and Manufacturer-Recommended Target Doses for Fluoxetine Indication Dose Depression in adults start at 20 mg per day and stay at this target dose (can increase to a maximum of to 80 mg per day) Depression in children start at 10 mg per day and can increase up to 20 mg per day OCD in adults start at 20 mg per day and can increase up to 60 mg per day OCD in children start at 10 mg per day and can increase up to 60 mg per day Bulimia nervosa 60 mg per day in the morning Panic disorder start at 10 mg per day with a target dose of 20 mg per day (maximum 60 mg per day) Modifications If you have liver disease, your doctor may prescribe a lower dose of fluoxetine for you than the standard recommended dose for your age and condition. A lower fluoxetine dose is also suggested if you are elderly or if you have multiple medical illnesses. How to Take and Store Fluoxetine tablets should be stored at a temperature between 68 degrees F to 77 degrees F and kept away from light. It can be taken with or without food. If you miss a dose, take it as soon as you remember. But if it is nearly time for your next dose, skip the missed dose and only take your next dose at its scheduled time. Never take two doses at the same time. Side Effects Fluoxetine is generally a safe medication, but it may cause side effects, some of which can be dangerous or life-threatening. Common Be sure to call your doctor if you experience side effects of fluoxetine. According to the manufacturer, the most common side effects of fluoxetine are: Abnormal dreams or insomnia Anorexia (decreased appetite or reduced eating) or nausea Nervousness or anxietyDry mouth A rash Tiredness or yawning Sweating A tremor General weakness Diarrhea Indigestion or heartburn Flu syndrome, sinusitis, or a sore throat Abnormal ejaculation or impotenceDiminished libidoLow blood pressure Severe Some side effects of fluoxetine are dangerous for your health. You should not abruptly stop taking the medication if you develop severe side effects, but you should get urgent medical attention. Serious side effects of fluoxetine include: Suicidal thoughts Serotonin syndrome Seizures Mania Bleeding Angle closure glaucomaLong QT syndromeHyponatremiaSevere weight loss Adverse Effects of Fluoxitine Warnings and Interactions It is best not to stop taking fluoxetine abruptly. You should talk to your doctor about a schedule for discontinuing fluoxetine if you plan to stop taking it. You can experience dizziness, balance problems, or mood disruption when you stop taking fluoxetine. Black Box Warning Fluoxetine has a black box warning for suicidal thoughts and behaviors in children, adolescents, and young adults. They should be monitored for the emergence or worsening suicidal thoughts and behaviors. Drug interactions include: Other serotonergic drugs: Fluoxetine can interfere with the action of other medications that interact with serotonin, and the combination can lead to an increased risk of serotonin syndrome. Pimozide and thioridazine: Fluoxetine can increase the levels of pimozide and thioridazine. Also, if fluoxetine is taken with either of these medications, the combination can increase the risk of a prolonged QT interval.Haloperidol and clozapine: Fluoxetine can raise the levels of these antipsychotic medications.Phenytoin and carbamazepine: Fluoxetine can raise the levels of these anti-seizure medications.Monoamine oxidase inhibitors (MAOIs): MAOIs antidepressants work differently from SSRIs. If you are switching between an MAOI and fluoxetine, you will need a break of about two weeks between stopping an MAOI and beginning fluoxetine, or for up to six weeks when stopping fluoxetine and starting an MAOI. Having both in your system can increase the risk of serotonin syndrome.Tricyclic antidepressants (TCAs): These antidepressant levels can be altered when they are taken together or when one is started within a few weeks of stopping the other. Diazepam and alprazolam: These antianxiety medications can interact with fluoxetine, potentially increasing their levels and adverse side effects. Was this page helpful? Thanks for your feedback! Sign up for our Health Tip of the Day newsletter, and receive daily tips that will help you live your healthiest life. Sign Up You're in! Thank you, {{form.email}}, for signing up. There was an error. Please try again. What are your concerns? Other Inaccurate Hard to Understand Submit Article Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Food and Drug Administration. Fluoxetine label. Updated January 2017. Lazarevic V, Mantas I, Flais I, Svenningsson P. Fluoxetine suppresses glutamate- and GABA-mediated neurotransmission by altering SNARE complex. Int J Mol Sci. 2019;20(17):4247. doi:10.3390/ijms20174247 Food and Drug Administration. Prozac label. Al Zaabi MSR, Sridhar SB, Tadross TM. Assessment of incidence, causality, severity, and preventability of suspected adverse drug reactions to antidepressant medications in a psychiatry outpatient setting of a secondary care hospital. J Pharm Bioallied Sci. 2020;12(2):131-138. doi:10.4103/jpbs.JPBS_196_19