Does Cimetidine Interact with Midazolam?
Cimetidine and Midazolam have a moderate drug interaction according to U.S. FDA drug labeling data. Inhibits P450-3A4 enzyme system, increasing midazolam steady-state concentration and prolonging sedation by decreasing plasma clearance. The mechanism involves p450-3a4 enzyme inhibition. Patients taking both medications should consult their healthcare provider before starting, stopping, or changing the dosage of either drug. This information is based on official FDA drug labeling sourced from OpenFDA and the NIH National Library of Medicine.
- Severity
- Moderate
- Cimetidine Class
- Histamine-2 Receptor Antagonist
- Midazolam Class
- Benzodiazepine
- Management
- Monitor for effects
- Data Source
- U.S. FDA via OpenFDA
How This Interaction Works
The interaction between Cimetidine and Midazolam occurs because p450-3a4 enzyme inhibition. Clinically, this means inhibits p450-3a4 enzyme system, increasing midazolam steady-state concentration and prolonging sedation by decreasing plasma clearance. This is classified as a moderate interaction. While it may not require stopping either medication, your healthcare provider should be aware you are taking both so they can monitor for potential effects and adjust treatment if necessary.
What To Tell Your Doctor or Pharmacist
If you are taking Cimetidine and your doctor is considering prescribing Midazolam (or vice versa), make sure to:
- Inform your doctor and pharmacist of all current medications, including over-the-counter drugs and supplements
- Ask whether the benefits of combining these medications outweigh the risks for your specific situation
- Ask what symptoms to watch for that would indicate the interaction is causing problems
- Ask whether any dosage adjustments are needed
- Never stop or change either medication without first consulting your healthcare provider