Atomoxetine and Diphenhydramine interaction
Atomoxetine and Diphenhydramine: the Atomoxetine prescribing label 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 Atomoxetine (Atomoxetine hydrochloride) label · effective 2026-04-03
Strong CYP2D6 Inhibitors Prevention or Management With concomitant use of atomoxetine oral solution and a strong CYP2D6 inhibitor 1 , increase the titration interval [see Dosage and Administration (2.5) and Clinical Pharmacology (12.3) ] .
Concomitant use of atomoxetine oral solution and a strong CYP2D6 inhibitor increases atomoxetine exposure [see Dosage and Administration (2.5) and Clinical Pharmacology (12.3) ] .
Strong CYP2D6 Inhibitors: With concomitant of atomoxetine oral solution and strong CYP2D6 inhibitors, increase the titration intervals.
See www.fda.gov/CYPandTransporterInteractingDrugs for examples of strong CYP2D6 inhibitors.
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.