For educational use only. MedTime is not medical advice. Consult a licensed clinician or pharmacist before making medication decisions.

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Antidepressant
Oral

Fluoxetine

SSRI

Also sold as Prozac

Onset of effect
7 days – 4 weeks
Felt/clinical effect
Tmax (peak blood level)
6 hr – 8 hr
Pharmacokinetic peak
Duration of effect
1 day
Per single dose

Cumulative therapeutic effect

Mood/anxiety benefit typically develops over 4–6 weeks of daily use.

Effect timeline

Approximate single-dose timeline. Onset shows when effects are felt; Tmax shows when blood levels peak.

6 hr12 hr18 hr
Onset of effectTmax (peak blood level)Wears off

Notes

Very long half-life; no taper needed.

What this is

Fluoxetine is a ssri given by the oral route. It's typically used in the antidepressant category.

What the numbers mean

After one oral dose you'd typically start noticing the effect in 7 days – 4 weeks. The drug reaches its highest blood level in about 6 hr – 8 hr, and a single dose usually keeps working for around 1 day.

Practical tips

Take consistently — the full benefit builds over time, not from a single dose. Swallow with water; check the label for food restrictions. Long-acting — take at roughly the same time each day for steady levels.

Important

Don't combine with other products in the same drug class without checking with a pharmacist. Stop and seek medical advice if you have an unexpected reaction, severe side effect, or symptoms that don't improve.

All timings are approximate population ranges for a typical adult dose. Individual response varies with age, genetics, formulation, food, and other medications.

Typical dosing

Source: OpenFDA drug label · adult dosing unless noted

Doses vary by age, weight, kidney/liver function, and indication. Don't change your dose without talking to your prescriber.

Verify on the exact label used:DailyMed search·OpenFDA record

Side effects & warnings

Source: OpenFDA drug label

Verify on the exact label used:DailyMed search·OpenFDA record

Educational information only — not medical advice. Times vary by person, dose, and formulation. Always consult a doctor or pharmacist for personal guidance.