Fluvoxamine and Mexiletine interaction
Fluvoxamine and Mexiletine: 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 Fluvoxamine (fluvoxamine maleate) label · effective 2026-04-23
Mexiletine: Monitor serum mexiletine levels ( 5.8 ).
Mexiletine: The effect of steady-state fluvoxamine (50 mg b.i.d. for 7 days) on the single dose pharmacokinetics of mexiletine (200 mg) was evaluated in 6 healthy Japanese males.
The clearance of mexiletine was reduced by 38% following coadministration with fluvoxamine compared to mexiletine alone.
If fluvoxamine and mexiletine are coadministered, serum mexiletine levels should be monitored.
Mexiletine: See Warnings and Precautions ( 5.8 ) .
From the Mexiletine (Mexiletine Hydrochloride) label · effective 2026-01-15
In a formal, single-dose interaction study (n = 6 males) the clearance of mexiletine was decreased by 38% following the coadministration of fluvoxamine, an inhibitor of CYP1A2.
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.