A Boxed Warning concerning lactic acidosis was added to the label for Metformin Hydrochloride, effective 2026-06-19. This warning highlights postmarketing cases of metformin-associated lactic acidosis, which have resulted in death, hypothermia, hypotension, and resistant bradyarrhythmias. The label also notes that the onset of this condition is often subtle.
Background
Metformin Hydrochloride is a medication often used as a component in combination therapies. An example includes canagliflozin and metformin hydrochloride (Invokamet, Invokamet XR).
What this means
The addition of a Boxed Warning for lactic acidosis to the Metformin Hydrochloride label underscores the serious nature of this adverse event. Clinicians prescribing Metformin Hydrochloride, whether as a standalone medication or as part of combination drugs like canagliflozin and metformin hydrochloride, must maintain a high index of suspicion for symptoms of lactic acidosis. The warning specifically mentions outcomes such as death, hypothermia, hypotension, and resistant bradyarrhythmias. The label also indicates that the onset of metformin-associated lactic acidosis is often subtle, necessitating careful monitoring and patient education regarding potential signs and symptoms.
Source
The information regarding this label revision was obtained from the FDA, as documented on DailyMed. The revised label for Metformin Hydrochloride became effective on 2026-06-19, and is accessible via dailymed.nlm.nih.gov.