Drug interactions
Atazanavir + Isoniazid
Severity: Minor
Atazanavir and Isoniazid: minor interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Isoniazid may weakly inhibit CYP3A4, but with boosted or unboosted atazanavir the clinical effect is expected to be small. Both drugs can cause hepatotoxicity, and atazanavir causes indirect hyperbilirubinemia.
What this interaction means in plain words
Atazanavir and Isoniazid have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Atazanavir belongs to Anti Virals; Isoniazid belongs to Anti Bacterial.
Why it happens
Weak CYP3A4 inhibition by isoniazid; additive hepatic toxicity is the more relevant concern.
What to do
No dose change is needed. Monitor liver enzymes and bilirubin during combined therapy.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
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Other interactions of Isoniazid
Other interactions of Atazanavir
- Alfuzosin + Atazanavir Contraindicated
- Atazanavir + Avanafil Contraindicated
- Atazanavir + Dronedarone Contraindicated
- Atazanavir + Eletriptan Contraindicated
- Atazanavir + Eplerenone Contraindicated
- Atazanavir + Ergotamine Contraindicated
Frequently asked questions
Can I take Atazanavir with Isoniazid?
MediHelp rates the interaction as minor. Atazanavir and Isoniazid have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Isoniazid may weakly inhibit CYP3A4, but with boosted or unboosted atazanavir the clinical effect is expected to be small. Both drugs can cause hepatotoxicity, and atazanavir causes indirect hyperbilirubinemia.
How serious is the interaction between Atazanavir and Isoniazid?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: No dose change is needed. Monitor liver enzymes and bilirubin during combined therapy.
What other medicines interact with Isoniazid?
MediHelp also lists interactions of Isoniazid with, for example, Bacillus calmette-guerin substrain tice, Benzhydrocodone / acetaminophen, Carbamazepine. The full list is on the Isoniazid page.
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