Does Cimetidine Interact with Letrozole?
Cimetidine and Letrozole have a minor drug interaction according to U.S. FDA drug labeling data. Pharmacokinetic interaction study showed no clinically significant effect on letrozole pharmacokinetics. 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
- Minor
- Cimetidine Class
- Histamine-2 Receptor Antagonist
- Letrozole Class
- Aromatase Inhibitor
- Management
- Generally manageable
- Data Source
- U.S. FDA via OpenFDA
What To Tell Your Doctor or Pharmacist
If you are taking Cimetidine and your doctor is considering prescribing Letrozole (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
- Never stop or change either medication without first consulting your healthcare provider