Doxepin and Isoniazid interaction
Doxepin and Isoniazid: the Doxepin 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 Doxepin (Silenor) label · effective 2026-04-21
Co-administration with Monoamine Oxidase Inhibitors (MAOIs): Do not administer if patient is taking MAOIs or has used MAOIs within the past two weeks.
Co-administration with Monoamine Oxidase Inhibitors (MAOIs) Serious side effects and even death have been reported following the concomitant use of certain drugs with MAO inhibitors.
Do not administer SILENOR if patient is currently on MAOIs or has used MAOIs within the past two weeks.
The exact length of time may vary depending on the particular MAOI dosage and duration of treatment.
DRUG INTERACTIONS MAO inhibitors: SILENOR should not be administered in patients on MAOIs within the past two weeks.
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.