Quick Facts
Generic NameFluoxetine
Brand NameProzac
Drug ClassSSRI
FDA Approved1987
Starting Dose20mg/day
Typical Range20–80mg/day
Max Dose80mg/day
Half-Life2–6 days (longest SSRI)
MetabolismCYP2D6 (major), CYP2C9
Generic Available2001
What Is Prozac?
Fluoxetine (brand name Prozac) is a selective serotonin reuptake inhibitor (SSRI) prescribed for depression, ocd, panic disorder, and other psychiatric conditions. First SSRI (1987). Longest half-life — virtually no discontinuation syndrome. FDA-approved for pediatric depression (8+) and OCD (7+). Only SSRI approved for bulimia. Active metabolite norfluoxetine extends effective half-life. Potent CYP2D6 inhibitor (drug interactions).
At Psychiatry Telemed, fluoxetine is prescribed and monitored by board-certified psychiatrists who understand the nuances of SSRI pharmacology — selecting the right dose, managing side effects, monitoring drug interactions, and optimizing your treatment through consistent monthly medication management appointments.
Fluoxetine (Prozac) — SSRI medication for psychiatric care
ManufacturerEli Lilly
How Prozac Affects Neurotransmitters
How Prozac Works
Fluoxetine selectively inhibits serotonin reuptake with the longest half-life of any SSRI (2–6 days including active metabolite norfluoxetine). This extended half-life provides natural protection against missed-dose withdrawal and produces the smoothest blood level profile of any SSRI.
Efficacy: Prozac vs. Comparators
Efficacy Comparison
Response & remission rates vs. comparators (Cipriani et al. meta-analysis)
Data from published meta-analyses. Individual response may vary.
Conditions Treated with Prozac
Depression
FDA-approved for MDD in adults and adolescents (8+). First SSRI approved in the US.
Learn About DepressionBulimia Nervosa
FDA-approved for bulimia nervosa (60mg). Also used off-label for BED.
Learn About Bulimia NervosaConsidering Prozac?
Board-certified psychiatrists can determine if fluoxetine is right for you.
Dosage Information
| Indication | Starting Dose | Typical Range | Maximum |
|---|---|---|---|
| Depression | 20mg/day | 20–80mg/day | 80mg/day |
| OCD | 20mg/day | 20–80mg/day | 80mg/day |
| Panic Disorder | 20mg/day | 20–80mg/day | 80mg/day |
| Bulimia Nervosa | 20mg/day | 20–80mg/day | 80mg/day |
Brain Regions Targeted by Prozac
Side Effects
Like all medications, fluoxetine has potential side effects. Most are mild, occur early in treatment, and resolve within 1–2 weeks. Your psychiatrist monitors at every appointment.
Common Side Effects
NauseaHeadacheInsomniaAnxiety/NervousnessDrowsinessDiarrheaDry Mouth
Less Common
TremorSexual DysfunctionAppetite ChangesSweatingRash
Serious (Seek Immediate Help)
Serotonin SyndromeSuicidal Thoughts (under 25)Mania ActivationAbnormal BleedingHyponatremiaQTc (rare)
Side Effect Profile: Prozac vs. Class Average
Side Effect Profile
Incidence rates from FDA prescribing information vs. class average
Percentages from clinical trial data. Actual experience may differ.
⚠️ FDA Black Box Warning
Antidepressants may increase suicidal thinking in young adults under 25.
Drug Interactions
Major Interactions
MAOIs (contraindicated, 5-week washout due to long half-life), CYP2D6 substrates (fluoxetine potently inhibits 2D6), thioridazine, pimozide
CYP Metabolism
Potent CYP2D6 inhibitor. Moderate CYP2C9/2C19 inhibitor. Significant drug interaction potential — more than sertraline or escitalopram. 5-week washout needed before MAOI.
Alcohol
Avoid alcohol during fluoxetine treatment. Both affect the CNS, increasing sedation and impairing judgment.
Generic Versions & Cost
Generic fluoxetine available since 2001. Approximate cost: $4–10/month. FDA-certified bioequivalent to brand-name Prozac.
Starting Prozac: What to Expect
First Weeks
Fluoxetine is typically started at 20mg/day and increased gradually. Common initial side effects usually improve within 1–2 weeks. Full therapeutic benefit develops over 4–8 weeks.
When to Contact Your Psychiatrist
Contact your psychiatrist for: worsening depression/anxiety, thoughts of self-harm, unusual agitation, severe side effects, or any concerning changes.
Stopping Prozac Safely
Never stop fluoxetine abruptly. Your psychiatrist will develop a gradual tapering schedule to minimize discontinuation effects.
Timeline: When Prozac Starts Working
Timeline to Effectiveness
Expected improvement trajectory over the first 8 weeks
Based on clinical trial data. Full therapeutic effects may take 6–8 weeks.
Get Prozac from a Board-Certified Psychiatrist
At Psychiatry Telemed, fluoxetine is prescribed following comprehensive evaluation. All Florida via HIPAA-compliant telepsychiatry. 1–3 days. $200 eval, $100 follow-up.
Frequently Asked Questions
Prescribed for depression, ocd, panic disorder, bulimia nervosa.
Typically 2–4 weeks for initial improvement, 4–8 weeks for full benefit.
Common: nausea, headache, insomnia, anxiety/nervousness, drowsiness. Most resolve within 1–2 weeks.
No. Not habit-forming but should not be stopped abruptly — gradual tapering recommended.
First SSRI (1987). Longest half-life — virtually no discontinuation syndrome. FDA-approved for pediatric depression (8+) and OCD (7+). Only SSRI approved for bulimia. Active metabolite norfluoxetine e
Alcohol should be avoided — increases sedation, impairs judgment, and may worsen symptoms.
Resources
Medical Disclaimer: Educational only. Consult a psychiatrist before starting/stopping medication. Crisis: call 988 or 911.
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