Recently, interest in healthfoods has been growing but as their use has increased many problems have arisen, one of them potential interactions between health foods and pharmaceuticals, and there have been reports of health foods containing pharmaceutical substances from time to time.
In April 2005, a 72-year-old man with diabetes mellitus was hospitalized at Fukuoka University Chikushi Hospital for hypoglycemia. The patient had been taking glimepiride, an antidiabetic sulfonylurea, as well as a Chinese health food product (“Qiao Qi Jiao Nang”) before being hospitalized. No health hazards had ever been reported for this health food. However, during our investigation of the cause of hypoglycemia in the patient, we detected an unknown compound in a methanol extract of the healthfood and it was identified as glibenclamide, another sulfonylurea drug, in thin layer chromatography, high performance liquid chromatography (HPLC), 1H-nuclear magnetic resonance (1H-NMR) and 13C-NMR. As measured by HPLC, the glibenclamide content of each capsule of the healthfood was about 2.6 mg. Since the patient had taken 6 capsules per day, the glibenclamide intake was assumed to be about 15.6 mg/day, which exceeds the maximal dose of glibenclamide in Japan. We therefore speculated that the hypoglycemia in the patient was due to the combination of glimepiride and the high dose of glibenclamide in the capsules.
As many patients assume that health foods are not harmful in any way, it is necessary for pharmacists to clearly inform them of risks of taking health foods together with drugs as well as the benefits.
