Drug interactions
Erythromycin + Rifapentine
Severity: Moderate
Erythromycin and Rifapentine: 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
Rifapentine induces CYP3A4 and can substantially reduce erythromycin concentrations, risking loss of antibacterial effect. The interaction is a loss of efficacy rather than toxicity.
What this interaction means in plain words
Erythromycin and Rifapentine 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.
Erythromycin belongs to Anti Bacterial; Rifapentine belongs to Anti Bacterial.
Why it happens
Rifapentine induces CYP3A4 and P-glycoprotein, increasing erythromycin clearance.
What to do
Monitor for treatment failure and consider an alternative antibiotic not dependent on CYP3A4 metabolism, such as azithromycin or a non-macrolide.
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 Erythromycin
- Conivaptan + Erythromycin Contraindicated
- Dihydroergotamine intranasal + Erythromycin Contraindicated
- Dihydroergotamine + Erythromycin Contraindicated
- Domperidone + Erythromycin Contraindicated
- Dronedarone + Erythromycin Contraindicated
- Droperidol + Erythromycin Contraindicated
Other interactions of Rifapentine
- Ledipasvir-sofosbuvir + Rifapentine Contraindicated
- Lorlatinib + Rifapentine Contraindicated
- Lurasidone + Rifapentine Contraindicated
- Ranolazine + Rifapentine Contraindicated
- Rifapentine + Sofosbuvir-velpatasvir Contraindicated
- Rifapentine + Sofosbuvir-velpatasvir-voxilaprevir Contraindicated
Frequently asked questions
Can I take Erythromycin with Rifapentine?
MediHelp rates the interaction as moderate. Erythromycin and Rifapentine 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. Rifapentine induces CYP3A4 and can substantially reduce erythromycin concentrations, risking loss of antibacterial effect. The interaction is a loss of efficacy rather than toxicity.
How serious is the interaction between Erythromycin and Rifapentine?
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 for treatment failure and consider an alternative antibiotic not dependent on CYP3A4 metabolism, such as azithromycin or a non-macrolide.
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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