Cimetidine and Midazolam interaction
Cimetidine and Midazolam: the Midazolam prescribing label describes an interaction that usually calls for monitoring, a dose change, or spacing the doses.
Usually manageable with monitoring or a dose change. Tell your pharmacist you take both.
What the FDA labels say
From the Midazolam (Midazolam in Sodium Chloride) label · effective 2025-07-31
The effect of single oral doses of 800 mg cimetidine and 300 mg ranitidine on steady-state concentrations of midazolam was examined in a randomized crossover study (n=8).
Cimetidine increased the mean midazolam steady-state concentration from 57 to 71 ng/mL.
Cytochrome P450-3A4 Inhibitors : May result in prolonged sedation due to decreased plasma clearance of midazolam.
Cytochrome P450-3A4 Inhibitors Concomitant administration with drugs that are known to inhibit the P450-3A4 enzyme system, such as cimetidine (not ranitidine), erythromycin, diltiazem, verapamil, ketoconazole and itraconazole, may result in prolonged sedation due to a decrease in plasma clearance of midazolam.
No change in choice reaction time or sedation index was detected after dosing with the H2 receptor antagonists.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.