Drug interactions
Erythromycin + Isoniazid
Severity: Minor
Erythromycin 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
A clinically meaningful rise in erythromycin levels from isoniazid is not well established. Isoniazid is mainly a weak inhibitor of CYP enzymes and has little recognized effect on erythromycin.
What this interaction means in plain words
Erythromycin 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.
Erythromycin belongs to Anti Bacterial; Isoniazid belongs to Anti Bacterial.
Why it happens
Possible weak CYP3A4 inhibition by isoniazid; not well established.
What to do
No routine change is needed. Monitor for erythromycin adverse effects such as gastrointestinal upset and hepatotoxicity when both are used together.
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 Erythromycin
- Conivaptan + Erythromycin Contraindicated
- Dihydroergotamine intranasal + Erythromycin Contraindicated
- Dihydroergotamine + Erythromycin Contraindicated
- Domperidone + Erythromycin Contraindicated
- Dronedarone + Erythromycin Contraindicated
- Droperidol + Erythromycin Contraindicated
Other interactions of Isoniazid
Frequently asked questions
Can I take Erythromycin with Isoniazid?
MediHelp rates the interaction as minor. Erythromycin 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. A clinically meaningful rise in erythromycin levels from isoniazid is not well established. Isoniazid is mainly a weak inhibitor of CYP enzymes and has little recognized effect on erythromycin.
How serious is the interaction between Erythromycin 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 routine change is needed. Monitor for erythromycin adverse effects such as gastrointestinal upset and hepatotoxicity when both are used together.
What other medicines interact with Erythromycin?
MediHelp also lists interactions of Erythromycin with, for example, Conivaptan, Dihydroergotamine intranasal, Dihydroergotamine. The full list is on the Erythromycin page.
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