Does Cimetidine Interact with Metformin?
CDI records a major classification for Cimetidine and Metformin. The stored summary is: Reduces metformin clearance by inhibiting renal tubular transport, increasing systemic exposure and lactic acidosis risk. The mechanism involves oct2/mate inhibitor that interferes with renal elimination of metformin. Patients taking both medications should consult their healthcare provider before starting, stopping, or changing the dosage of either drug. This record was extracted from drug labeling through openFDA. NIH/NLM RxNorm is used for drug identities. The summary and severity classification are CDI's processed information, not a verbatim source quotation. Product, route, and patient circumstances matter.
- Severity
- Major
- Cimetidine Class
- Histamine-2 Receptor Antagonist
- Management
- Close medical supervision required
- Data Source
- U.S. FDA via OpenFDA
Recorded Mechanism
OCT2/MATE inhibitor that interferes with renal elimination of metformin
What To Tell Your Doctor or Pharmacist
If you are taking Cimetidine and your doctor is considering prescribing Metformin (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 how frequently you should be monitored while these are co-prescribed
- Ask whether any dosage adjustments are needed
- Never stop or change either medication without first consulting your healthcare provider