Isoniazid and Ziprasidone interaction
Isoniazid and Ziprasidone: the Ziprasidone 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 Ziprasidone label · effective 2026-06-09
• Concomitant use of monoamine oxidase inhibitors (MAOIs), or use within 14 days of stopping MAOIs.
Monoamine Oxidase Inhibitors (MAOIs) Ziprasidone is contraindicated in patients taking, or within 14 days of stopping, MAOIs (including the MAOIs linezolid and intravenous methylene blue) because of an increased risk of serotonin syndrome [see Warnings and Precautions ( 5.4 ), Drug Interaction ( 7.3 )].
The concomitant use of ziprasidone with MAOIs is contraindicated.
Ketoconazole Ketoconazole, a potent inhibitor of CYP3A4, at a dose of 400 mg QD for 5 days, increased the AUC and C max of ziprasidone by about 35 to 40%.
John’s Wort) and with drugs that impair metabolism of serotonin, i.e., monoamine oxidase inhibitors (MAOIs) [see Contraindications ( 4.3 ), Adverse Reactions (6.2 ), Drug Interactions ( 7.3 )].
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.