A boxed warning regarding the risk of lactic acidosis has been added to the label for Metformin Hydrochloride Extended Release, effective 2026-05-22. This significant label revision highlights the potential for serious adverse events, including death, hypothermia, hypotension, and resistant bradyarrhythmias, associated with metformin-associated lactic acidosis.
Background
The boxed warning, effective 2026-05-22, explicitly states: 'WARNING: LACTIC ACIDOSIS 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 '. This warning emphasizes the serious and potentially fatal nature of this adverse event associated with metformin use.
What this means
The implementation of a boxed warning represents the strongest caution the FDA can mandate for a drug, indicating a serious and potentially life-threatening risk. For Metformin Hydrochloride Extended Release, this means healthcare professionals must exercise heightened awareness and vigilance regarding the risk of lactic acidosis. Clinicians should carefully assess patient risk factors, monitor for early signs and symptoms, and educate patients about the potential for this severe adverse event. The warning underscores the importance of prompt recognition and management of lactic acidosis, which can manifest with non-specific symptoms and progress rapidly to severe outcomes, including death, hypothermia, hypotension, and resistant bradyarrhythmias. This label revision reinforces the need for a thorough understanding of the drug's safety profile and appropriate patient counseling.
Source
The information regarding this label revision was obtained from the FDA. This update to the label for Metformin Hydrochloride Extended Release, specifically the addition of a boxed warning, became effective on 2026-05-22 and is accessible via dailymed.nlm.nih.gov.