Fluvoxamine and Isoniazid interaction
Fluvoxamine and Isoniazid: the Fluvoxamine prescribing label flags 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 Fluvoxamine (fluvoxamine maleate) label · effective 2026-04-23
Serotonin Syndrome and Monoamine Oxidase Inhibitors (MAOIs) The use of MAOIs intended to treat psychiatric disorders with Fluvoxamine Maleate Tablets or within 14 days of stopping treatment with Fluvoxamine Maleate Tablets is contraindicated because of an increased risk of serotonin syndrome.
The use of Fluvoxamine Maleate Tablets within 14 days of stopping an MAOI intended to treat psychiatric disorders is also contraindicated [see Dosage and Administration ( 2.4 ), Warnings and Precautions ( 5.2 )] .
Starting Fluvoxamine Maleate Tablets in a patient who is being treated with MAOIs such as linezolid or intravenous methylene blue is also contraindicated because of an increased risk of serotonin syndrome [see Dosage and Administration ( 2.5 ), Warnings and Precautions ( 5.2 )] .
Serotonin Syndrome and MAOIs: Do not use MAOIs intended to treat psychiatric disorders with Fluvoxamine Maleate Tablets or within 14 days of stopping treatment with Fluvoxamine Maleate Tablets.
Do not use Fluvoxamine Maleate Tablets within 14 days of stopping an MAOI intended to treat psychiatric disorders.
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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.