Metformin and Ranolazine Interaction

Drug interaction information between Metformin and Ranolazine.

Metformin and Ranolazine have a documented minor interaction in FDA labeling.

FDA drug labeling documents a minor-severity interaction between Metformin and Ranolazine. This page displays the available source-record category and label text. The category is not an individual risk estimate or medication-combination direction.

Drug A

Metformin

Biguanide

Drug B

Ranolazine

Late Sodium Current Inhibitor (Antianginal)

How They Interact

Ranolazine slows down how quickly your body removes metformin, which can cause the medicine to build up in your blood.

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.

Frequently Asked Questions

What SPL severity band is on file for Metformin + Ranolazine?

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?

Ranolazine has 31 labeled pairs on file vs Metformin's 27. In the minor band specifically: Metformin has 17 (also Topiramate, Dolutegravir, Cimetidine, Phenytoin); Ranolazine has 12 (also Diltiazem, Fluconazole, Verapamil, Cyclosporine).

What mechanism field is on file for Metformin and Ranolazine?

Ranolazine slows down how quickly your body removes metformin, which can cause the medicine to build up in your blood.

Ranolazine carries more major-labeled pairs than Metformin

SPL source-record counts only. This page's band is minor · classes on file: Metformin (Biguanide); Ranolazine (Late Sodium Current Inhibitor (Antianginal)).

Ranolazine has 12 major-labeled pairs vs Metformin's 0. This page itself is in the minor band, not the major band.

Metformin

0 major · 10 moderate · 17 minor · 27 total

Ranolazine

12 major · 7 moderate · 12 minor · 31 total

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.