Mexiletine and Cimetidine Interaction

Drug interaction information between Mexiletine and Cimetidine.

Mexiletine and Cimetidine have a documented minor interaction in FDA labeling.

FDA drug labeling documents a minor-severity interaction between Mexiletine 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.

Drug A

Mexiletine

Class IB Antiarrhythmic

Drug B

Cimetidine

H2 Receptor Antagonist

How They Interact

Cimetidine can change how your liver handles mexiletine, which might cause mexiletine levels to rise or fall.

FDA Label Information

Concurrent administration of cimetidine and mexiletine has been reported to increase, decrease, or leave unchanged mexiletine plasma levels; therefore patients should be followed carefully during concurrent therapy.

Frequently Asked Questions

What SPL severity band is on file for Mexiletine + 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 Mexiletine's 14. In the minor band specifically: Mexiletine has 13 (also Propranolol, Digoxin, Propafenone, Theophylline); Cimetidine has 63 (also Albendazole, Alogliptin, Alosetron, Alprazolam).

What mechanism field is on file for Mexiletine and Cimetidine?

Cimetidine can change how your liver handles mexiletine, which might cause mexiletine levels to rise or fall.

Cimetidine carries more major-labeled pairs than Mexiletine

SPL source-record counts only. This page's band is minor · classes on file: Mexiletine (Class IB Antiarrhythmic); Cimetidine (H2 Receptor Antagonist).

Cimetidine has 4 major-labeled pairs vs Mexiletine's 0. This page itself is in the minor band, not the major band.

Mexiletine

0 major · 1 moderate · 13 minor · 14 total

Cimetidine

4 major · 10 moderate · 63 minor · 77 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.