Citalopram and Isoniazid interaction
Citalopram and Isoniazid: the Citalopram 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 Citalopram label · effective 2025-10-07
Citalopram Capsules is contraindicated in patients: taking, or within 14 days of stopping, MAOIs (including MAOIs such as linezolid or intravenous methylene blue) because of an increased risk of serotonin syndrome [see Warnings and Precautions ( 5.3 ), Drug Interactions ( 7 )] . taking pimozide because of risk of QT prolongation [see Drug Interactions ( 7 )]…
Concomitant use of monoamine oxidase inhibitors (MAOIs) or use within 14 days of discontinuing an MAOI.
Avoid use of Citalopram Capsules in CYP2C19 poor metabolizers, patients receiving concomitant cimetidine or another CYP2C19 inhibitor, patients with hepatic impairment, and patients who are greater than 60 years of age, because Citalopram Capsules are only available in a 30 mg dose strength and dosage adjustments are not possible [see Drug Interactions ( 7 ),…
The concomitant use of Citalopram Capsules with MAOIs is contraindicated.
CYP2C19 inhibitors and CYP2C19 poor metabolizers: Avoid concomitant use.
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.