DOUBLE‐BLIND TRIAL OF METFORMIN IN THE THERAPY OF NONKETOTIC DIABETICS

Seventeen diabetics with normal renal function who were aged from 31 to 79 years who were already receiving from 10 mg to 20 mg of glibenclamide daily participated in a double‐blind crossover trial of metformin (500 mg twice a day) for two months. After two months of metformin therapy, mean fasting and postprandial blood glucose levels were significantly lower than control values (9.9 mmol/L versus 12.4 mmol/L and 13.5 mmol/L versus 16.4 mmol/L; P= <0.001 and <0.01 respectively). In contrast, there was no difference between blood glucose levels while the patients received placebo and control blood glucose levels. There was no significant difference in effect on weight, fasting plasma lactate levels, fasting or postprandial plasma insulin levels, or the occurrence of side effects, between metformin and placebo. It is concluded that in selected diabetics whose condition is inadequately controlled with sulphonylurea therapy, significant improvement in diabetic control can be obtained by the addition of metformin in a low dose of 500 mg twice a day.