Carvedilol and Diltiazem Interaction
Drug interaction information between Carvedilol and Diltiazem.
Carvedilol and Diltiazem have a documented minor interaction in FDA labeling.
FDA drug labeling documents a minor-severity interaction between Carvedilol and Diltiazem. 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
Both drugs slow down the heart's electrical signals and lower blood pressure. This can cause the heart to beat too slowly or change its rhythm.
FDA Label Information
( 7.6 ) Verapamil- or diltiazem-type calcium channel blockers may affect ECG and/or blood pressure. 7.7 Calcium Channel Blockers Conduction disturbance (rarely with hemodynamic compromise) has been observed when carvedilol tablet is coadministered with diltiazem. As with other β-blocker, if carvedilol tablet is administered with calcium channel blockers of the verapamil or diltiazem type, it is recommended that ECG and blood pressure be monitored.
Carvedilol Also Interacts With
- Clonidine moderate
- Fluoxetine minor
- Paroxetine minor
- Fluconazole minor
- Verapamil minor
Diltiazem Also Interacts With
- Ezetimibe major
- Ezetimibe/Simvastatin major
- Simvastatin major
- Theophylline major
- Rifampin moderate
Frequently Asked Questions
What SPL severity band is on file for Carvedilol + Diltiazem?
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?
Diltiazem has 46 labeled pairs on file vs Carvedilol's 13. In the minor band specifically: Carvedilol has 12 (also Fluoxetine, Paroxetine, Fluconazole, Verapamil); Diltiazem has 35 (also Buspirone, Pravastatin, Lovastatin, Cyclosporine).
What mechanism field is on file for Carvedilol and Diltiazem?
Both drugs slow down the heart's electrical signals and lower blood pressure. This can cause the heart to beat too slowly or change its rhythm.
Diltiazem carries more major-labeled pairs than Carvedilol
SPL source-record counts only. This page's band is minor · classes on file: Carvedilol (Beta-Blocker (Alpha/Beta)); Diltiazem (Calcium Channel Blocker).
Diltiazem has 4 major-labeled pairs vs Carvedilol's 0. This page itself is in the minor band, not the major band.
0 major · 1 moderate · 12 minor · 13 total
- Other minor peers for Carvedilol
- Fluoxetine
- Paroxetine
- Fluconazole
- Verapamil
4 major · 7 moderate · 35 minor · 46 total
- Other minor peers for Diltiazem
- Buspirone
- Pravastatin
- Lovastatin
- Cyclosporine
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.