Suicide commitment with metformin: our experience with five cases.

Area of Science:

• Pharmacology
• Endocrinology
• Toxicology

Background:

• Biguanides, including metformin, are widely used oral antihyperglycemic agents for managing diabetes mellitus and prediabetes.
• Metformin's popularity surged after phenformin's withdrawal due to safety concerns, establishing it as a first-line treatment.
• Common side effects of metformin include gastrointestinal issues like diarrhea and dyspepsia, affecting up to 30% of patients.

Observation:

• The most serious adverse effect associated with biguanides is lactic acidosis.
• Phenformin was withdrawn from the market due to a high incidence of lactic acidosis (40-65 per 100,000 patient-years).
• Metformin-induced lactic acidosis is typically observed in patients with hepatic or renal failure, or in cases of intentional overdose.

Findings:

• This report presents a series of five patients who intentionally ingested high doses of metformin in suicide attempts.
• The cases highlight a specific scenario where metformin can lead to significant lactate accumulation, distinct from typical therapeutic use.
• Analysis of these cases provides insights into the toxicological profile of metformin at supratherapeutic levels.

Implications:

• Understanding metformin's risk profile in overdose situations is crucial for emergency medicine and toxicology.
• These findings underscore the importance of monitoring patients with pre-existing conditions and in cases of intentional misuse.
• Further research into the mechanisms and management of metformin-induced lactic acidosis in overdose is warranted.