Metformin

378 interactions 1 explained in plain English 428 cited references
Also sold as: Fortamet® Glucophage Glucophage® Glumetza Glumetza® Riomet Riomet® Trijardy® (as a combination product containing Empagliflozin, Linagliptin, Metformin)
About Metformin

Metformin is a biguanide medication used to help control blood sugar levels in type 2 diabetes. Read the full Metformin 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 →

Major

Metformin Abemaciclib Verzenio Increased metFORMIN exposure and an increased risk of lactic acidosis Details Metformin Acetazolamide Diamox® Sequels® An increased risk of lactic acidosis and reduced serum bicarbonate Details Metformin Abiraterone Abirtega An increased risk of severe hypoglycemia Details Metformin Arimoclomol Increased OCT2 substrate exposure Details Metformin Brinzolamide Ophthalmic Azopt An increased risk of lactic acidosis and reduced serum bicarbonate Details Metformin Capmatinib Tabrecta Increased exposure of MATE1 and MATE2K substrates and risk of increased adverse reactions Details Metformin Chloroquine Aralen® Hypoglycemia Details Metformin Delafloxacin Baxdela Changes in blood glucose and increased risk of hypoglycemia or hyperglycemia Details Metformin Delafloxacin Injection Baxdela Changes in blood glucose and increased risk of hypoglycemia or hyperglycemia Details Metformin Digoxin Cardoxin® Increased digoxin exposure Details Metformin Dofetilide Tikosyn Increased dofetilide exposure and an increased risk of cardiotoxicity (QT prolongation, torsades de pointes, cardiac arrest) Details Metformin Dolutegravir Juluca® (as a combination product containing dolutegravir, rilpivirine) Increased metFORMIN exposure and an increased risk of lactic acidosis Details Metformin Dorzolamide Ophthalmic Trusopt® Ocumeter® Plus An increased risk of lactic acidosis and reduced serum bicarbonate Details Metformin Gatifloxacin Ophthalmic Zymar® Changes in blood glucose and increased risk of hypoglycemia or hyperglycemia Details Metformin Gemifloxacin Factive Changes in blood glucose and increased risk of hypoglycemia or hyperglycemia Details Metformin Hydroxychloroquine Plaquenil Enhanced hypoglycemic effect of antidiabetics and an increased risk of hypoglycemia Details Metformin Insulin Degludec (Rdna Origin) Injection Ryzodeg® (as a combination product containing Insulin Degludec and Insulin Aspart) An increased risk of hypoglycemia Details Metformin Insulin Detemir (Rdna Origin) Injection Levemir An increased risk of hypoglycemia Details Metformin Insulin Glulisine (Rdna Origin) Injection Apidra An increased risk of hypoglycemia Details Metformin Iomeprol Injection Increased risk of metFORMIN-induced lactic acidosis Details Metformin Lanreotide Injection Somatuline An increased risk of hypoglycemia and impaired glucose regulation Details Metformin Levofloxacin Levaquin Changes in blood glucose and increased risk of hypoglycemia or hyperglycemia Details Metformin Levofloxacin Injection Levaquin Changes in blood glucose and increased risk of hypoglycemia or hyperglycemia Details Metformin Abiraterone Acetate Abirtega An increased risk of severe hypoglycemia Details Metformin Abiraterone Acetate, Micronized Abirtega An increased risk of severe hypoglycemia Details Metformin Apalutamide Erleada Increased metFORMIN exposure and an increased risk of lactic acidosis Details Metformin Bictegravir Increased metFORMIN exposure and an increased risk of lactic acidosis Details Metformin Brinzolamide An increased risk of lactic acidosis and reduced serum bicarbonate Details Metformin Bupropion Aplenzin Reduced renal clearance of OCT2 substrates Details Metformin Cimetidine Tagamet Increased metFORMIN exposure and an increased risk of lactic acidosis Details Metformin Ciprofloxacin Changes in blood glucose and increased risk of hypoglycemia or hyperglycemia Details Metformin Dasabuvir Increased risk of lactic acidosis Details Metformin Diatrizoate Increased risk of acute decrease in renal function and occurrence of lactic acidosis Details Metformin Dichlorphenamide An increased risk of lactic acidosis and reduced serum bicarbonate Details Metformin Dorzolamide An increased risk of lactic acidosis and reduced serum bicarbonate Details Metformin Enoxacin Changes in blood glucose and increased risk of hypoglycemia or hyperglycemia Details Metformin Ethiodized Oil Increased risk of acute decrease in renal function and occurrence of lactic acidosis Details Metformin Fedratinib Inrebic Increased metFORMIN exposure and an increased risk of metFORMIN-related adverse events Details Metformin Fexinidazole Increased metformin exposure Details Metformin Gatifloxacin Zymaxid Changes in blood glucose and increased risk of hypoglycemia or hyperglycemia Details

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Educational information only, not medical advice. Always confirm interactions with your pharmacist or prescriber before making any change to your medications.