[A case of hypoglycemia caused by the accidental ingestion of glimepiride in an elderly dementia patient diagnosed based on the serum glimepiride concentration].

A 77-year-old man being treated for Alzheimer-type dementia and an old cerebral infarction was admitted to our hospital due to disturbance of consciousness. The patient's Mini-mental State Examination and Hasegawa Dementia Scale scores were 23 and 17 points, respectively. His blood glucose level was low (18 mg/dl), with a relatively high insulin level (15.2 µU/ml). Computed tomography and an 18-hour fasting test showed no signs of insulinoma. Since his wife had been taking medications for dementia and diabetes, including Glimepiride, we considered the possibility that he may have taken glimepiride by mistake. Five months later, he was admitted again due to severe hypoglycemia with a relatively high insulin level (23.4 µU/ml). More than 660 g of glucose and 100 mg of hydrocortisone were administered, and the hypoglycemia resolved approximately 24 hours after admission. Again, there were no signs of insulinoma. We asked Sanofi-Aventis to measure the level of glimepiride in a blood sample obtained six hours after admission. Glimepiride was detected at a concentration of 24.48 ng/ml, which roughly corresponded to the accidental ingestion of 6 mg of the drug. We were later informed by the patient's home doctor that he had visited the emergency department of another prefecture hospital with the same symptoms. Thereafter, the couple received counseling by their home doctor, and the hypoglycemia has not recurred since. Given the increase in the number of elderly households, an increase in the number of episodes of accidental ingestion of medicine is expected. Clinicians should be aware of the potential for accidental exposure to drugs prescribed to other family members especially, in elderly patients.