Metronidazole

278 interactions 832 cited references
Also sold as: Flagyl Flagyl® Flagyl® 375 Flagyl® ER Likmez MetroCream MetroGel MetroLotion Noritate Nuvessa Nydamax Rosadan Vandazole
About Metronidazole

Metronidazole is an antibiotic used to treat bacterial and parasitic infections in various parts of the body, including the reproductive and gastrointestinal systems. Read the full Metronidazole 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: Terfenadine Saquinavir Piperaquine Pimozide Thioridazine Sparfloxacin
15 Contraindicated 244 Major 19 Moderate
All (278) Contraindicated (15) Major (244) Moderate (19)

Moderate

Metronidazole Cholestyramine Resin Locholest® Decreased metronidazole effectiveness Details Metronidazole Cyclosporine Injection Atopica An increased risk of cycloSPORINE toxicity (nephrotoxicity, cholestasis, paresthesias) Details Metronidazole Cyclosporine Ophthalmic Cequa An increased risk of cycloSPORINE toxicity (nephrotoxicity, cholestasis, paresthesias) Details Metronidazole Dihydroergotamine Injection DHE-45® Injection Increased plasma concentrations of ergot derivatives and increased risk of ergotism (nausea, vomiting, vasospastic ischemia) Details Metronidazole Dihydroergotamine Nasal Spray Migranal Increased plasma concentrations of ergot derivatives and increased risk of ergotism (nausea, vomiting, vasospastic ischemia) Details Metronidazole Lixisenatide Injection Adlyxin® Delayed therapeutic effect Details Metronidazole Methylergonovine Methergine Increased plasma concentrations of ergot derivatives and increased risk of ergotism (nausea, vomiting, vasospastic ischemia) Details Metronidazole Anisindione An increased risk of bleeding Details Metronidazole Carbamazepine Carbatrol Increased carbamazepine serum concentrations and potential carbamazepine toxicity Details Metronidazole Cholestyramine Prevalite Decreased metronidazole effectiveness Details Metronidazole Cyclosporine Atopica An increased risk of cycloSPORINE toxicity (nephrotoxicity, cholestasis, paresthesias) Details Metronidazole Dicumarol An increased risk of bleeding Details Metronidazole Dihydroergotamine Brekiya Increased plasma concentrations of ergot derivatives and increased risk of ergotism (nausea, vomiting, vasospastic ischemia) Details Metronidazole Ergoloid Mesylates Alkergot® Increased plasma concentrations of ergot derivatives and increased risk of ergotism (nausea, vomiting, vasospastic ischemia) Details Metronidazole Ergonovine Increased plasma concentrations of ergot derivatives and increased risk of ergotism (nausea, vomiting, vasospastic ischemia) Details Metronidazole Ergotamine Ergomar Increased plasma concentrations of ergot derivatives and increased risk of ergotism (nausea, vomiting, vasospastic ischemia) Details Metronidazole Lixisenatide Delayed therapeutic effect Details Metronidazole Milk Thistle Reduced metronidazole and active metabolite exposure Details Metronidazole Phenindione An increased risk of bleeding Details

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