Phenformin-associated metabolic acidosis

Area of Science:

• Endocrinology
• Metabolic Disorders
• Pharmacology

Background:

• Phenformin is an oral antihyperglycemic agent used for type 2 diabetes.
• Metabolic acidosis is a serious complication that can arise in patients treated with phenformin.

Purpose of the Study:

• To investigate the occurrence and characteristics of metabolic acidosis in diabetic patients treated with phenformin.
• To evaluate the association between phenformin use and adverse metabolic complications.

Main Methods:

• Retrospective analysis of 18 consecutive diabetic patients admitted with metabolic acidosis.
• Assessment of lactic acidosis and ketoacidosis markers, including plasma 3-hydroxybutyrate levels.
• Correlation of survival with clinical factors such as shock and severity of lactic acidosis.

Main Results:

• All 18 patients presented with metabolic acidosis, including lactic acidosis and coexisting ketoacidosis (average plasma 3-hydroxybutyrate 7.1 mmol/L).
• Most patients did not have marked hyperglycemia, necessitating insulin and glucose treatment.
• Survival correlated with the absence of shock; 10 patients had no identifiable cause for illness other than phenformin treatment.

Conclusions:

• Phenformin treatment is associated with a high incidence of severe metabolic acidosis (lactic acidosis and ketoacidosis).
• The findings raise significant concerns regarding the safety and continued use of phenformin in diabetic patients.
• Management should consider insulin and glucose due to potential hypoglycemia and hyperglycemia.