[Lactic acidosis associated with fenformin therapy].

Irreversible lactic acidosis occurred in two phenformin-treated diabetics. In the first case, blood creatinine was 3 mg % ml, arterial blood pH was 7,12 and ketostix was negative; in the second case, blood creatinine was 1,3 mg% ml, arterial blood pH was 7,22 and ketostix was negative. Diabetic patients to be treated with phenformin must always be carefully selected and this treatment should be reserved for cases where there is a precise indication. Lactic acidosis may occur even in the presence of almost normal serum creatinine concentrations.