Metformin and Cimetidine Interaction
Drug interaction information between Metformin and Cimetidine.
Metformin and Cimetidine have a documented minor interaction in FDA labeling.
FDA drug labeling documents a minor-severity interaction between Metformin and Cimetidine. This page displays the available source-record category and label text. The category is not an individual risk estimate or medication-combination direction.
How They Interact
Cimetidine prevents your body from getting rid of metformin normally, which can lead to higher levels of the drug in your system.
FDA Label Information
Examples: Ranolazine, vandetanib, dolutegravir, and cimetidine. ( 7 ) Drugs that reduce metformin clearance (such as ranolazine, vandetanib, dolutegravir, and cimetidine) may increase the accumulation of metformin.
Metformin Also Interacts With
- Bictegravir/Emtricitabine/Tenofovir moderate
- Dolutegravir/Lamivudine moderate
- Empagliflozin moderate
- Empagliflozin/Linagliptin moderate
- Ertugliflozin moderate
Cimetidine Also Interacts With
- Levofloxacin major
- Posaconazole major
- Risperidone major
- Valproate major
- Empagliflozin moderate
Frequently Asked Questions
What SPL severity band is on file for Metformin + Cimetidine?
Compiled FDA labeling labels this pair minor. That is a source-record field, not an individual medication-combination decision.
Which drug in this pair has the larger labeled-interaction portfolio?
Cimetidine has 77 labeled pairs on file vs Metformin's 27. In the minor band specifically: Metformin has 17 (also Topiramate, Dolutegravir, Ranolazine, Phenytoin); Cimetidine has 63 (also Albendazole, Alogliptin, Alosetron, Alprazolam).
What mechanism field is on file for Metformin and Cimetidine?
Cimetidine prevents your body from getting rid of metformin normally, which can lead to higher levels of the drug in your system.
Cimetidine carries more major-labeled pairs than Metformin
SPL source-record counts only. This page's band is minor · classes on file: Metformin (Biguanide); Cimetidine (H2 Receptor Antagonist).
Cimetidine has 4 major-labeled pairs vs Metformin's 0. This page itself is in the minor band, not the major band.
0 major · 10 moderate · 17 minor · 27 total
- Other minor peers for Metformin
- Topiramate
- Dolutegravir
- Ranolazine
- Phenytoin
4 major · 10 moderate · 63 minor · 77 total
- Other minor peers for Cimetidine
- Albendazole
- Alogliptin
- Alosetron
- Alprazolam
Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. This registry does not provide individual medication-combination directions.
Read our methodology - how this data is sourced, computed, and verified.