[Lactic acidosis after administration of buformine (author's transl)]

An 85-year-old female diabetic was admitted in coma, having been on antidiabetic treatment with the biguanide derivative "Silubin retard", 600 mg/d, for one-and-a-half months. The anion deficiency was 57 mmol/l, pH 6.9, suggesting the diagnosis of lactic acidosis in the absence of other causes of metabolic acidosis. Blood lactic acid levels of more than 16.65 mmol/l (150 mg/100 ml) confirmed the diagnosis. Administration of 875 mmol sodium bicarbonate over 12 hours corrected the deficiency. On admission to hospital there had been slight pre-renal failure. Myocardial infarction developed as a result of tissue hypoxia but did not prove clinically important. On the second day there were signs of a compensated disseminated intravascular coagulopathy with upper gastro intestinal haemorrhage. The woman died suddenly 18 days later of pulmonary embolism.