Acarbose reduces elevated testosterone serum concentrations in hyperinsulinaemic premenopausal women: a pilot study

In seven hyperinsulinaemic, hypertestosteronaemic premenopausal patients, we tested the effect of an attenuation of insulin serum concentrations by long-term treatment with the enteral disaccharidase inhibitor acarbose on serum concentrations of total and free testosterone, dehydroepiandrosterone sulphate (DHEAS) and sex hormone-binding globulin (SHBG). The subjects showed typical features of hyperinsulinaemia-hypertestosteronaemia syndrome, including elevated concentrations of insulin and testosterone, normal concentrations of DHEAS and suppressed SHBG concentrations. The patients were orally treated with an initial dosage of 50 mg acarbose/ day, which was gradually increased to a maximum of 300 mg/day. Blood was sampled at week 6 (under a dosage of 150 mg acarbose/day) and at week 20 of treatment. A significant reduction in the increase of glucose and insulin concentrations, determined after administration of a standard oral 100 g glucose load, was found at week 6 (P < 0.02, P < 0.00007) and at week 20 (P < 0.04, P < 0.003) of therapy and was associated with a significant decrease of total and free testosterone at week 20 (P < 0.04, P < 0.01). Concentrations of both DHEAS and SHBG remained nearly unchanged. In conclusion, it was shown that a decline of ovarian hypertestosteronaemia was achieved in association with a flattening of the postprandial glucose and insulin increase by long-term treatment with acarbose. Side effects were limited to abdominal distension and flatulence and were absent using a low dosage of 50 mg acarbose/ meal (3 x 50 mg/day).