The label for Metformin Hydrochloride was revised on 2026-05-06 to include a new Boxed Warning regarding the risk of lactic acidosis. This warning highlights that postmarketing cases of metformin-associated lactic acidosis have resulted in death, hypothermia, hypotension, and resistant bradyarrhythmias.
What this means
The addition of a Boxed Warning to the Metformin Hydrochloride label is a significant update for clinicians and patients. This warning specifically addresses the severe and potentially fatal risk of lactic acidosis associated with metformin use. Postmarketing surveillance has identified cases where this condition led to serious outcomes, including death, hypothermia, hypotension, and resistant bradyarrhythmias. Healthcare providers are advised to be aware of the signs and symptoms, which may include malaise, myalgia, respiratory distress, somnolence, and abdominal distress. Patients should be counseled on these potential risks and instructed to seek immediate medical attention if they experience any symptoms. This label change reinforces the importance of careful patient selection, monitoring of renal function, and awareness of contraindications to minimize the risk of this serious adverse event.
Source
This information is based on a label revision for Metformin Hydrochloride, effective 2026-05-06, as documented by the FDA. The updated label can be found on dailymed.nlm.nih.gov.