Insulin autoimmune syndrome after the third therapy with methimazole.

In 1986, a 26-year-old female had been diagnosed as having Graves' disease and had been treated with methimazole for four months. After the treatment with propylthiouracil for another four months, she had been treated with methimazole once again. She was in complete remission for two years. She again experienced symptoms of hyperthyroidism, and treatment with methimazole was started again. On the thirteenth day after treatment, she experienced hypoglycemic attacks with skin eruption. The plasma glucose was 57 mg/dl, 125I-Insulin binding 69%, free IRI 196 microU/ml. The patient had the HLA-DRB1*0406.