Cimetidine

83 interactions 6 explained in plain English
Also sold as: Tagamet
Dr. Brian Staiger, PharmD, BCPS
Medically reviewed by Dr. Brian Staiger, PharmD, BCPS · Updated Jul 4, 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 →

Major

Cimetidine Acetaminophen And Codeine Capital® & Codeine Explained Increased codeine exposure and increased or reduced active metabolite (morphine) exposure Details Cimetidine Buprenorphine Belbuca Explained Increased buprenorphine exposure and an increased risk of buprenorphine-related adverse events Details Cimetidine Relugolix Orgovyx Explained Increased relugolix exposure Details Cimetidine Acalabrutinib Calquence Reduced acalabrutinib exposure Details Cimetidine Bedaquiline Sirturo Increased bedaquiline exposure Details Cimetidine Bosutinib Bosulif Increased or reduced bosutinib exposure Details Cimetidine Budesonide Entocort Increased budesonide exposure Details Cimetidine Budesonide Nasal Spray Rhinocort Increased budesonide exposure Details Cimetidine Budesonide Oral Inhalation Pulmicort Increased budesonide exposure Details Cimetidine Capecitabine Xeloda An increased risk of fluorouracil toxicity Details Cimetidine Carmustine BiCNU Increased bone marrow toxicity (eg, leukopenia and neutropenia) Details Cimetidine Carmustine Implant Gliadel Increased bone marrow toxicity (eg, leukopenia and neutropenia) Details Cimetidine Cefuroxime Ceftin® Decreased cefuroxime axetil exposure Details Cimetidine Chloroquine Aralen® Chloroquine toxicity Details Cimetidine Cyclosporine Injection Atopica An increased risk of cycloSPORINE toxicity (renal dysfunction, cholestasis, paresthesias) Details Cimetidine Cyclosporine Ophthalmic Cequa An increased risk of cycloSPORINE toxicity (renal dysfunction, cholestasis, paresthesias) Details Cimetidine Dabigatran Pradaxa® Increased dabigatran exposure and an increased risk of bleeding Details Cimetidine Dabigatran Etexilate Increased dabigatran exposure and an increased risk of bleeding Details Cimetidine Dasatinib Phyrago Reduced dasatinib exposure Details Cimetidine Digoxin Cardoxin® Increased digoxin exposure Details Cimetidine Doxorubicin Adriamycin Increased DOXOrubicin exposure and an increased risk of DOXOrubicin-related adverse reactions Details Cimetidine Erlotinib Tarceva Reduced erlotinib exposure Details Cimetidine Fentanyl Transdermal Patch Duragesic® Increased fentaNYL exposure and an increased risk of prolonged opioid effects Details Cimetidine Finerenone Kerendia Increased finerenone exposure and an increased risk of finerenone-related adverse effects Details Cimetidine Fluorouracil Adrucil An increased risk of fluorouracil toxicity Details Cimetidine Fluorouracil Injection Adrucil An increased risk of fluorouracil toxicity Details Cimetidine Fluorouracil Topical Carac An increased risk of fluorouracil toxicity Details Cimetidine Gefitinib Iressa Decreased exposure of gefitinib Details Cimetidine Hydroxychloroquine Plaquenil Increased hydroxychloroquine exposure Details Cimetidine Infigratinib Truseltiq Decreased infigratinib plasma concentrations Details Cimetidine Ketoconazole Topical Extina® Foam Reduced ketoconazole exposure and reduced efficacy of ketoconazole Details Cimetidine Lefamulin Xenleta Increased lefamulin exposure and an increased risk of lefamulin-related adverse reactions Details Cimetidine Loperamide Diamode An increased loperamide exposure and an increased risk of loperamide-related adverse reactions Details Cimetidine Meloxicam Alloxate Increased meloxicam exposure and reduced meloxicam metabolic clearance Details Cimetidine Meloxicam Injection Alloxate Increased meloxicam exposure and reduced meloxicam metabolic clearance Details Cimetidine Metformin Fortamet® Increased metFORMIN exposure and an increased risk of lactic acidosis Details Cimetidine Methylergonovine Methergine Increased methylergonovine exposure Details Cimetidine Methylphenidate Adhansia XR® Altered pharmacodynamic and changes in release profile of methylphenidate Details Cimetidine Methylphenidate Transdermal Patch Daytrana Altered pharmacodynamic and changes in release profile of methylphenidate Details Cimetidine Metronidazole Flagyl Increased metroNIDAZOLE exposure Details

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