Diltiazem and Metoprolol Interaction

Drug interaction information between Diltiazem and Metoprolol.

Diltiazem and Metoprolol have a documented moderate interaction in FDA labeling.

FDA drug labeling documents a moderate-severity interaction between Diltiazem and Metoprolol. 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

Diltiazem

Calcium Channel Blocker

Drug B

Metoprolol

Beta-Blocker

How They Interact

Both of these medicines slow down your heart rate and the electrical signals that tell your heart when to beat. Taking them together can make your heart beat much slower than it should.

FDA Label Information

( 7.3 ) Concomitant use of glycosides, clonidine, and diltiazem and verapamil with beta-blockers can increase the risk of bradycardia. 7.4 Negative Chronotropes Digitalis glycosides, clonidine, diltiazem and verapamil slow atrioventricular conduction and decrease heart rate.

Frequently Asked Questions

What SPL severity band is on file for Diltiazem + Metoprolol?

Compiled FDA labeling labels this pair moderate. That is a source-record field, not an individual medication-combination decision.

Which drug in this pair has the larger labeled-interaction portfolio?

Diltiazem has 46 labeled pairs on file vs Metoprolol's 18. In the moderate band specifically: Diltiazem has 7 (also Rifampin, Digoxin, Ivabradine, Aprepitant); Metoprolol has 3 (also Clonidine, Verapamil).

What mechanism field is on file for Diltiazem and Metoprolol?

Both of these medicines slow down your heart rate and the electrical signals that tell your heart when to beat. Taking them together can make your heart beat much slower than it should.

Diltiazem carries more major-labeled pairs than Metoprolol

SPL source-record counts only. This page's band is moderate · classes on file: Diltiazem (Calcium Channel Blocker); Metoprolol (Beta-Blocker).

Diltiazem has 4 major-labeled pairs vs Metoprolol's 1. This page itself is in the moderate band, not the major band.

Diltiazem

4 major · 7 moderate · 35 minor · 46 total

Metoprolol

1 major · 3 moderate · 14 minor · 18 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.