Drug interactions
Cobimetinib + Erythromycin
Severity: Major
Cobimetinib and Erythromycin: major interaction.
Last updated Sources: US FDA label
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
Erythromycin, a moderate CYP3A inhibitor, can increase cobimetinib exposure and the risk of adverse effects such as hemorrhage, rhabdomyolysis and liver toxicity.
What this interaction means in plain words
Cobimetinib and Erythromycin can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Cobimetinib belongs to Oncology; Erythromycin belongs to Anti Bacterial.
Why it happens
Inhibition of CYP3A4 metabolism of cobimetinib by erythromycin.
What to do
Use a non-CYP3A-inhibiting antibiotic. If a short course is unavoidable, reduce cobimetinib to 20 mg daily as labeled and resume the usual dose afterwards.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Cobimetinib and Erythromycin, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
References
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 Cobimetinib
- Cobimetinib + Efavirenz Contraindicated
- Cobimetinib + Posaconazole Contraindicated
- Amobarbital + Cobimetinib Major
- Apalutamide + Cobimetinib Major
- Aprepitant + Cobimetinib Major
- Bosentan + Cobimetinib Major
Frequently asked questions
Can I take Cobimetinib with Erythromycin?
MediHelp rates the interaction as major. Cobimetinib and Erythromycin can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Erythromycin, a moderate CYP3A inhibitor, can increase cobimetinib exposure and the risk of adverse effects such as hemorrhage, rhabdomyolysis and liver toxicity.
How serious is the interaction between Cobimetinib and Erythromycin?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Use a non-CYP3A-inhibiting antibiotic. If a short course is unavoidable, reduce cobimetinib to 20 mg daily as labeled and resume the usual dose afterwards.
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.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
