Atomoxetine and Isoniazid interaction
Atomoxetine and Isoniazid: the Atomoxetine prescribing label flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Atomoxetine (Atomoxetine hydrochloride) label · effective 2026-04-03
Taking, or within 14 days of stopping, a monoamine oxidase inhibitor (MAOI) [see Drug Interactions (7) ] .
Contraindicated in patients ( 4 ): With known hypersensitivity to atomoxetine oral solution or other components of atomoxetine oral solution Taking or within 14 days of stopping, a monoamine oxidase inhibitor (MAOI) With narrow angle glaucoma.
Table 9: Clinically Significant Drug Interactions with Atomoxetine Oral Solution and Other Drugs Monoamine Oxidase Inhibitors (MAOIs) Prevention or Management Atomoxetine oral solution is contraindicated in patients taking MAOIs, including MAOIs such as linezolid or intravenous methylene blue, or in patients who stopped an MAOI within 14 days.
Monoamine Oxidase Inhibitors: Concomitant use contraindicated.
Mechanism and Clinical Effect(s) As with other drugs affecting brain monoamine concentrations, there have been reports of serious, sometimes fatal reactions (hyperthermia, rigidity, myoclonus, autonomic instability with fluctuations of vital signs, extreme agitation progressing to delirium/coma) with concomitant use of atomoxetine oral solution and an MAOI.
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.