Meclizine and Olanzapine and fluoxetine interaction
Meclizine and Olanzapine and fluoxetine: both prescribing labels describe an interaction that usually calls for monitoring, a dose change, or spacing the doses.
Usually manageable with monitoring or a dose change. Tell your pharmacist you take both.
What the FDA labels say
From the Meclizine (Meclizine Hydrochloride) label · effective 2026-06-12
• Coadministration of meclizine hydrochloride with other CNS depressants, including alcohol, may result in increased CNS depression ( 7.1 ).
CNS Depressants There may be increased CNS depression when meclizine hydrochloride is administered concurrently with other CNS depressants, including alcohol [see Warnings and Precautions (5.1) ] .
• CYP2D6 inhibitors: As meclizine is metabolized by CYP2D6, there is a potential for drug-drug interactions between meclizine hydrochloride and CYP2D6 inhibitors ( 7.2 ).
CYP2D6 Inhibitors Based on in-vitro evaluation, meclizine is metabolized by CYP2D6.
Therefore, there is a possibility for a drug interaction between meclizine hydrochloride and CYP2D6 inhibitors.
From the Olanzapine and fluoxetine label · effective 2026-03-31
Anticholinergic (antimuscarinic) Effects : Use with caution with other anticholinergic drugs and in patients with urinary retention, prostatic hypertrophy, constipation, history of paralytic ileus or related conditions ( 5.21 )
Most patients improved promptly with discontinuation of fluoxetine and/or adjunctive treatment with antihistamines or steroids, and all patients experiencing these reactions were reported to recover completely.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.