Darifenacin and Diltiazem Interaction

Drug interaction information between Darifenacin and Diltiazem.

Darifenacin and Diltiazem have a documented minor interaction in FDA labeling.

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

Drug A

Darifenacin

Anticholinergic (Overactive Bladder)

Drug B

Diltiazem

Calcium Channel Blocker

How They Interact

Diltiazem interferes with a liver protein that breaks down darifenacin. This can cause a minor increase in darifenacin levels in your body.

FDA Label Information

No dosing adjustments are recommended in the presence of moderate CYP3A4 inhibitors (for example, erythromycin, fluconazole, diltiazem and verapamil) [see Dosage and Administration (2) and Clinical Pharmacology (12.3) ] .

Frequently Asked Questions

What SPL severity band is on file for Darifenacin + 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 Darifenacin's 18. In the minor band specifically: Darifenacin has 15 (also Fluoxetine, Duloxetine, Estradiol, Paroxetine); Diltiazem has 35 (also Buspirone, Pravastatin, Lovastatin, Cyclosporine).

What mechanism field is on file for Darifenacin and Diltiazem?

Diltiazem interferes with a liver protein that breaks down darifenacin. This can cause a minor increase in darifenacin levels in your body.

Diltiazem carries more major-labeled pairs than Darifenacin

SPL source-record counts only. This page's band is minor · classes on file: Darifenacin (Anticholinergic (Overactive Bladder)); Diltiazem (Calcium Channel Blocker).

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

Darifenacin

0 major · 3 moderate · 15 minor · 18 total

Diltiazem

4 major · 7 moderate · 35 minor · 46 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.