The short answer
There is no established evidence that zinc reduces fluoxetine absorption or effectiveness. A small mixed-antidepressant trial instead found better depression scores with zinc, but it did not measure fluoxetine levels.
What this answer covers
Oral supplemental zinc with fluoxetine; distinguish elemental zinc amount and formulation from total salt weight.
- Supplement or preparation
- Zinc
- Medication ingredient
- fluoxetine
What the human study tested
A twelve-week trial added zinc or placebo to citalopram or fluoxetine treatment. Overall depression scores favored zinc by week twelve.
What it did not test
The study did not measure fluoxetine concentrations or intestinal absorption and did not report a separate fluoxetine result. It cannot demonstrate either a chelation interaction or guaranteed benefit for this exact pair.
No required interval follows
There is no validated fluoxetine-zinc spacing rule in these sources. Follow your prescription instructions and ask the pharmacist about your specific zinc product.
Supplement for an identified reason
A favorable small trial is not a reason to start zinc automatically. Discuss your diet, reason for supplementation and total elemental zinc amount with the clinician; do not change fluoxetine to compensate for a presumed interaction.
Evidence and practical considerations
Absorption & effectiveness
Current reduced-absorption/effectiveness claim is insufficient; favorable mixed-drug efficacy evidence does not establish an exact fluoxetine dose recommendation.
- Exact scope
- Oral supplemental zinc with fluoxetine; distinguish elemental zinc amount and formulation from total salt weight. with Exact oral fluoxetine hydrochloride capsules. RxNorm IN 4493/PIN 227224 hydrochloride capsules. Active norfluoxetine and prolonged elimination matter. Not the combined olanzapine product.
- Medication form and route
- oral
- Timing or duration
- Source-specific single-dose, repeated-dose and observational exposures distinguished.
What remains uncertain
- No drug PK measurements, exact fluoxetine allocation or medication-specific subgroup outcome.
Factors that may matter: preparation and plant part; clinical indication; dose; other medicines; baseline alertness.
Read the supporting source summaries
Source 1: current product label
dailymed.nlm.nih.gov · Source check Sep 10, 2026
Population: People prescribed oral fluoxetine.
Exact label names tryptophan and St John’s wort in serotonin warnings, warns about bleeding and mania, and describes long elimination of fluoxetine and norfluoxetine.
How this applies: RxNorm IN 4493/PIN 227224 hydrochloride capsules. Active norfluoxetine and prolonged elimination matter. Not the combined olanzapine product.
No universal supplement interval, event rate or preparation equivalence established. Original label distinguishes warnings from measured pair-specific results.
Source 2: original human study
pubmed.ncbi.nlm.nih.gov · Source check Sep 10, 2026
Population: Forty-four depressed adults randomized to mixed SSRI regimens, thirty-eight completing follow-up.
Depression scores favored zinc at week twelve; no fluoxetine-specific subgroup or drug-concentration measurement.
How this applies: Only the named drug, preparation, route and measured endpoints apply.
Small mixed-drug study; efficacy outcome is not absorption measurement, and exact fluoxetine allocation is not reported.
Research assessment: · Open full citations ↗
Review and change history
- Publication status
- Published research summary
- Clinical review
- Not yet recorded
| Date | Update |
|---|---|
| Article prepared | |
| Current exact available claims adjudicated using original captures and explicit identity and comparator limits. | |
| Research summary published |
Article revision: 97ced8f98df65cc9
This guide brings together the evidence records used by our interaction checker. Each finding retains its own preparation limits, research date, and source summaries.
Full citations require verification. Reading this answer and the source summaries does not.
Taking other supplements or medications?
Use the checker to explore your other combinations. Ask a pharmacist to review the exact products, amounts and medical conditions in your complete list.
Open the interaction checkerInformation, not medical advice. Do not change prescribed treatment based on this guide.