OverviewDosageSide EffectsInteractionsHalf-Life

Generic Name: Fluoxetine hydrochloride

Brands: Prozac

Class: Selective serotonin reuptake inhibitor (SSRI)

Availability: Prescription needed

Molecular Formula: C17H18F3NO

Substance UNII: I9W7N6B1KJ

What is Prozac?

Prozac is a selective serotonin reuptake inhibitor (SSRI). It is the trade name of the drug fluoxetine.

What is Prozac Used For?

According to the FDA, Prozac is indicated (recommended for the treatment of) major depressive disorder (MDD), obsessive compulsive disorder (OCD), bulimia nervosa (bulimia), and panic disorder (with or without agoraphobia present). Further, patients can use fluoxetine in combination with olanzapine (Zyprexa) as part of the treatment for bipolar I disorder and treatment-resistant depression.

How Does Prozac Work?

Prozac (fluoxetine hydrochloride) is an SSRI, a class of antidepressants formally known as selective serotonin reuptake inhibitors. Although experts do not know Prozac’s exact mechanism of action, they believe that this drug helps inhibit the reabsorption (reuptake) of serotonin, the “feel-good chemical.” As such, fluoxetine extends how long serotonin stays in the central nervous system (CNS). Notably, stabilizing serotonin levels in the CNS tends to elevate and stabilize mood. In fact, research shows that many people with depression and related disorders have lower levels of serotonin. 

How Long Does it Take for Prozac to Work?

To feel the full effects of Prozac, patients need to wait roughly 4 to 6 weeks; this adjustment phase may be marked by unpleasant symptoms. That said, some patients have reported noticing improvements within a week or two of starting this drug.

Do Not Use Prozac If:

This medication may not be the right choice for everyone. According to the FDA, the following should not use fluoxetine:

  • Patients who are currently taking monoamine oxidase inhibitors (MAOIs) or have taken MAOIs within 14 days (2 weeks) of starting Prozac
  • People undergoing treatment with either linezolid (Zyvox) or intravenous (IV) methylene blue (ProvayBlue)
  • Patients taking pimozide (Orap)
  • Patients taking thioridazine

Please note that this list may not be complete, and there may be other situations where use of this drug is not advisable.

Disclaimer: this article does not constitute or replace medical advice. If you have an emergency or a serious medical question, please contact a medical professional or call 911 immediately. To see our full medical disclaimer, visit our Terms of Use page.

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