Buspirone and Diltiazem Interaction
Drug interaction information between Buspirone and Diltiazem.
Buspirone and Diltiazem have a documented minor interaction in FDA labeling.
FDA drug labeling documents a minor-severity interaction between Buspirone 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
Diltiazem prevents the body from breaking down buspirone properly, which causes buspirone levels to rise significantly.
FDA Label Information
Buspirone : In nine healthy subjects, diltiazem significantly increased the mean buspirone AUC 5.5-fold and C max 4.1-fold compared to placebo. The T 1/2 and T max of buspirone were not significantly affected by diltiazem. Enhanced effects and increased toxicity of buspirone may be possible during concomitant administration with diltiazem.
Buspirone Also Interacts With
- Tranylcypromine moderate
- Ziprasidone moderate
- Citalopram minor
- Darunavir minor
- Desvenlafaxine 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 Buspirone + 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 Buspirone's 17. In the minor band specifically: Buspirone has 15 (also Citalopram, Darunavir, Desvenlafaxine, Diphenoxylate/Atropine); Diltiazem has 35 (also Pravastatin, Lovastatin, Cyclosporine, Carbamazepine).
What mechanism field is on file for Buspirone and Diltiazem?
Diltiazem prevents the body from breaking down buspirone properly, which causes buspirone levels to rise significantly.
Diltiazem carries more major-labeled pairs than Buspirone
SPL source-record counts only. This page's band is minor · classes on file: Buspirone (Azapirone Anxiolytic); Diltiazem (Calcium Channel Blocker).
Diltiazem has 4 major-labeled pairs vs Buspirone's 0. This page itself is in the minor band, not the major band.
0 major · 2 moderate · 15 minor · 17 total
- Other minor peers for Buspirone
- Citalopram
- Darunavir
- Desvenlafaxine
- Diphenoxylate/Atropine
4 major · 7 moderate · 35 minor · 46 total
- Other minor peers for Diltiazem
- Pravastatin
- Lovastatin
- Cyclosporine
- Carbamazepine
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.