Drug interactions
Dapsone + Isoniazid
Severity: Moderate
Dapsone and Isoniazid: moderate 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 modestly increase dapsone exposure, and both drugs can cause peripheral neuropathy and hepatotoxicity. Dapsone also causes dose-related hemolysis and methemoglobinemia. They are often used together in practice, for example in mycobacterial infections, and the combination is usually manageable.
What this interaction means in plain words
Dapsone and Isoniazid can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Dapsone belongs to Anti Bacterial; Isoniazid belongs to Anti Bacterial.
Why it happens
Possible isoniazid inhibition of CYP-mediated dapsone metabolism plus overlapping neurotoxic and hepatotoxic effects.
What to do
Monitor liver function, blood counts and neuropathy symptoms. Consider pyridoxine supplementation and adjust dapsone if toxicity appears.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Isoniazid
Other interactions of Dapsone
- Bcg vaccine live + Dapsone Major
- Dapsone + Primaquine Major
- Apalutamide + Dapsone Moderate
- Belzutifan + Dapsone Moderate
- Bosentan + Dapsone Moderate
- Bupivacaine implant + Dapsone Moderate
Frequently asked questions
Can I take Dapsone with Isoniazid?
MediHelp rates the interaction as moderate. Dapsone and Isoniazid can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Isoniazid may modestly increase dapsone exposure, and both drugs can cause peripheral neuropathy and hepatotoxicity. Dapsone also causes dose-related hemolysis and methemoglobinemia. They are often used together in practice, for example in mycobacterial infections, and the combination is usually manageable.
How serious is the interaction between Dapsone and Isoniazid?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor liver function, blood counts and neuropathy symptoms. Consider pyridoxine supplementation and adjust dapsone if toxicity appears.
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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