Drug interactions
Erythromycin + Midazolam
Severity: Major
Erythromycin and Midazolam: 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 substantially increases midazolam exposure and prolongs its sedative effect, which may cause excessive sedation and respiratory depression. The effect is larger with oral midazolam than intravenous.
What this interaction means in plain words
Erythromycin and Midazolam 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 belongs to Anti Bacterial; Midazolam belongs to Central Nervous System.
Why it happens
Erythromycin inhibits intestinal and hepatic CYP3A4, reducing midazolam first-pass and systemic clearance.
What to do
Reduce the midazolam dose and titrate carefully with respiratory monitoring. Consider an alternative benzodiazepine not dependent on CYP3A4, such as lorazepam.
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?
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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 Midazolam
- Atazanavir + Midazolam Contraindicated
- Cobicistat + Midazolam Contraindicated
- Darunavir + Midazolam Contraindicated
- Elvitegravir / cobicistat / emtricitabine / tenofovir df + Midazolam Contraindicated
- Fosamprenavir + Midazolam Contraindicated
- Indinavir + Midazolam Contraindicated
Frequently asked questions
Can I take Erythromycin with Midazolam?
MediHelp rates the interaction as major. Erythromycin and Midazolam 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 substantially increases midazolam exposure and prolongs its sedative effect, which may cause excessive sedation and respiratory depression. The effect is larger with oral midazolam than intravenous.
How serious is the interaction between Erythromycin and Midazolam?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Reduce the midazolam dose and titrate carefully with respiratory monitoring. Consider an alternative benzodiazepine not dependent on CYP3A4, such as lorazepam.
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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