Colchicine and Diltiazem Interaction
Drug interaction information between Colchicine and Diltiazem.
Colchicine and Diltiazem have a documented minor interaction in FDA labeling.
FDA drug labeling documents a minor-severity interaction between Colchicine 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 blocks the proteins that normally break down colchicine in your body. This can cause colchicine levels to rise, increasing the risk of side effects.
FDA Label Information
Drug Interactions: Pharmacokinetic Parameters for Colchicine Tablets in the Presence of the Coadministered Drug Coadministered Drug Dose of Coadministered Drug (mg) Dose of Colchicine Tablets (mg) N % Change in Colchicine Concentrations from Baseline (Range: Min – Max) C max AUC 0-t Cyclosporine 100 mg single dose 0.6 mg single dose 23 270.0 (62.0 to 606.9) 259.0 (75.8 to 511.9) Clarithromycin 250 mg twice daily, 7 days 0.6 mg single dose 23 227.2 (65.7 to 591.1) 281.5 (88.7 to 851.6) Ketoconazole 200 mg twice daily, 5 days 0.6 mg single dose 24 101.7 (19.6 to 219.0) 212.2 (76.7 to 419.6)...
Colchicine Also Interacts With
- Clarithromycin major
- Darunavir major
- Itraconazole major
- Nirmatrelvir/Ritonavir major
- Atorvastatin moderate
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 Colchicine + 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 Colchicine's 28. In the minor band specifically: Colchicine has 15 (also Estradiol, Norethindrone, Ketoconazole, Verapamil); Diltiazem has 35 (also Buspirone, Pravastatin, Lovastatin, Cyclosporine).
What mechanism field is on file for Colchicine and Diltiazem?
Diltiazem blocks the proteins that normally break down colchicine in your body. This can cause colchicine levels to rise, increasing the risk of side effects.
Diltiazem's labeled portfolio outnumbers Colchicine
SPL source-record counts only. This page's band is minor · classes on file: Colchicine (Anti-Gout Agent); Diltiazem (Calcium Channel Blocker).
4 major · 9 moderate · 15 minor · 28 total
- Other minor peers for Colchicine
- Estradiol
- Norethindrone
- Ketoconazole
- 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.