Colesevelam

49 interactions 77 cited references
Also sold as: Welchol WelChol®
About Colesevelam

A bile acid sequestrant medication used to lower cholesterol and fatty substances in the blood and help control blood sugar in type 2 diabetes. Read the full Colesevelam drug information page →

Dr. Brian Staiger, PharmD, BCPS
Medically reviewed by Dr. Brian Staiger, PharmD, BCPS · Updated Aug 10, 2026 · Editorial policy · Data sources

Sources: FDA prescribing information (Structured Product Labeling), the published literature cited in each entry, DDInter 2.0 (a major open-access drug-interaction database), and legacy DrugBank interaction data distributed by the NIH's RxNav service (decommissioned in 2024) — analyzed and reviewed by our pharmacist team. How we build this library →

Most serious with: Bezafibrate Deferasirox Desogestrel Dienogest Drospirenone Elafibranor
29 Major 19 Moderate 1 Minor
All (49) Major (29) Moderate (19) Minor (1)

Moderate

Colesevelam Cholic Acid Decreased efficacy of cholic acid Details Colesevelam Cyclosporine Atopica Decreased cycloSPORINE exposure and plasma concentrations Details Colesevelam Diltiazem Cardizem Decreased diltiazem bioavailability Details Colesevelam Estetrol Decreased estetrol and drospirenone exposure Details Colesevelam Glimepiride Amaryl Decreased glimepiride exposure Details Colesevelam Glipizide Glucotrol Decreased glipiZIDE exposure Details Colesevelam Glyburide DiaBeta® Decreased glyBURIDE exposure and plasma concentrations Details Colesevelam Levothyroxine Ermeza Reduced levothyroxine exposure and reduced efficacy of levothyroxine Details Colesevelam Liothyronine Cytomel Decreased effectiveness of liothyronine Details Colesevelam Maralixibat Livmarli Reduced exposure and efficacy of maralixibat Details Colesevelam Metformin Fortamet® Increased exposure to extended-release metformin Details Colesevelam Obeticholic Acid Ocaliva Reduced exposure and efficacy of obeticholic acid Details Colesevelam Odevixibat Bylvay Reduced exposure and efficacy of odevixibat Details Colesevelam Olmesartan Medoxomil Benicar Decreased olmesartan medoxomil exposure Details Colesevelam Phenytoin Dilantin Decreased phenytoin exposure Details Colesevelam Warfarin Coumadin Reduced INR results Details Colesevelam Cyclosporine Injection Atopica Decreased cycloSPORINE exposure and plasma concentrations Details Colesevelam Cyclosporine Ophthalmic Cequa Decreased cycloSPORINE exposure and plasma concentrations Details Colesevelam Olmesartan Benicar Decreased olmesartan medoxomil exposure Details

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