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 →

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)

Major

Metronidazole Vemurafenib Zelboraf An increased risk of QT interval prolongation Details Metronidazole Venlafaxine An increased risk of QT interval prolongation Details Metronidazole Vepdegestrant Veppanu An increased risk of QT interval prolongation and an increased risk of torsade de pointes, polymorphic ventricular tachycardia, ot... Details Metronidazole Vilanterol An increased risk of QT interval prolongation Details Metronidazole Vinflunine An increased risk of QT interval prolongation Details Metronidazole Voclosporin Lupkynis An increased risk of QT interval prolongation Details Metronidazole Voriconazole Vfend An increased risk of QT interval prolongation Details Metronidazole Vorinostat Zolinza An increased risk of QT interval prolongation Details Metronidazole Warfarin Coumadin Increased warfarin exposure and INR, and an increased risk of bleeding Details Metronidazole Ziftomenib Komzifti An increased risk of QT interval prolongation and torsade de pointes Details Metronidazole Zotepine An increased risk of QT interval prolongation Details Metronidazole Zuclopenthixol An increased risk of QT interval prolongation Details Metronidazole Moxifloxacin Injection Avelox An increased risk of QT interval prolongation Details Metronidazole Moxifloxacin Ophthalmic Moxeza® An increased risk of QT interval prolongation Details Metronidazole Octreotide Injection Bynfezia An increased risk of QT interval prolongation Details Metronidazole Ofloxacin Ophthalmic Ocuflox An increased risk of QT interval prolongation Details Metronidazole Ofloxacin Otic Floxin® Otic An increased risk of QT interval prolongation Details Metronidazole Olodaterol Oral Inhalation Striverdi An increased risk of QT interval prolongation and an increased risk of ventricular arrhythmias Details Metronidazole Oxaliplatin Injection Eloxatin® Increased risk of QT-interval prolongation Details

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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