Last reviewed 2026-04-20 · How we verify

METFORMIN HYDROCHLORIDE

At a glance

Approved indications

No approved indications tracked.

Boxed warnings

• WARNING: LACTIC ACIDOSIS WARNING: LACTIC ACIDOSIS See full prescribing information for complete boxed warning . Postmarketing cases of metformin-associated lactic acidosis have resulted in death, hypothermia, hypotension, and resistant bradyarrhythmias. Symptoms included malaise, myalgias, respiratory distress, somnolence, and abdominal pain. Laboratory abnormalities included elevated blood lactate levels, anion gap acidosis, increased lactate/pyruvate ratio, and metformin plasma levels generally >5 mcg/mL. ( 5.1 ) Risk factors include renal impairment, concomitant use of certain drugs, age ≥65 years old, radiological studies with contrast, surgery and other procedures, hypoxic states, excessive alcohol intake, and hepatic impairment. Steps to reduce the risk of and manage metformin-associated lactic acidosis in these high-risk groups are provided in the Full Prescribing Information. ( 5.1 ) If lactic acidosis is suspected, discontinue ZITUVIMET and institute general supportive measures in a hospital setting. Prompt hemodialysis is recommended. ( 5.1 ) Postmarketing cases of metformin-associated lactic acidosis have resulted in death, hypothermia, hypotension, and resistant bradyarrhythmias. The onset of metformin-associated lactic acidosis is often subtle, accompanied only by nonspecific symptoms such as malaise, myalgias, respiratory distress, somnolence, and abdominal pain. Metformin-associated lactic acidosis was characterized by elevated blood lactate levels (>5 mmol/Liter), anion gap acidosis (without evidence of ketonuria or ketonemia), an increased lactate/pyruvate ratio, and metformin plasma levels generally >5 mcg/mL [see Warnings and Precautions ( 5.1 )] . Risk factors for metformin-associated lactic acidosis include renal impairment, concomitant use of certain drugs (e.g., carbonic anhydrase inhibitors such as topiramate), age 65 years old or greater, having a radiological study with contrast, surgery and other procedures, hypoxic states (e.g., acute congestive heart failure), excessive alcohol intake, and hepatic impairment. Steps to reduce the risk of and manage metformin-associated lactic acidosis in these high risk groups are provided in the full prescribing information [see Dosage and Administration ( 2.2 )>, Contraindications ( 4 ), Warnings and Precautions ( 5.1 ), Drug Interactions ( 7 ), and Use in Specific Populations ( 8.6 , 8.7 )] . If metformin-associated lactic acidosis is suspected, immediately discontinue ZITUVIMET and institute general supportive measures in a hospital setting. Prompt hemodialysis is recommended [see Warnings and Precautions ( 5.1 )] .

Common side effects

• Diarrhea
• Nausea/Vomiting
• Flatulence
• Asthenia
• Indigestion
• Abdominal Discomfort
• Headache
• Abnormal Stools
• Hypoglycemia
• Myalgia
• Lightheaded
• Dyspnea

Serious adverse events

• Lactic Acidosis
• Vitamin B12 Deficiency
• Cholestatic Liver Injury
• Hepatocellular Liver Injury
• Mixed Hepatocellular Liver Injury
• Palpitation

Key clinical trials

• Study to Evaluate the Effect of Repotrectinib on the Drug Levels of Transporter and CYP P450 Probe Substrates in Healthy Adult Participants (PHASE1)
• Metformin Hydrochloride in Preventing Oral Cancer in Patients With an Oral Premalignant Lesion (PHASE2)
• Modular Clinical Pharmacology Study to Evaluate the Drug-drug Interaction Potential and Relative Bioavailability of Saruparib (PHASE1)
• Effect of Local Application of 1% Metformin Gel on Implant Stability and Peri-implant Bone Density: A Randomized Controlled Study (NA)
• Comparative Evaluation of Topical Metformin and Topical Tranexamic Acid in Melasma (NA)
• Diabetes Management for Primary Healthcare Centers. (NA)
• Metformin and Chemotherapy in Treating Patients With Stage III-IV Ovarian, Fallopian Tube, or Primary Peritoneal Cancer (PHASE2)
• Metformin for People With CFRD on CFTR Modulator Therapy to Improve Ion Channel Function (PHASE2)

Primary sources

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