Liver injuries induced by herbal medicine, syo-saiko-to (xiao-chai-hu-tang).

Four patients treated with the herbal medicine syo-saiko-to (xiao-chai-hu-tang) exhibited acute drug-induced liver injury. The latent period was one and a half to three months. All of the patients showed a rise in aminotransferases after readministration or challenge test. The liver histology revealed centrilobular confluent necrosis or spotty necrosis, microvesicular fatty change, acidophilic degeneration, and a granuloma. Cholestasis was seen in two patients. The results of the [13C]aminopyrine breath test, performed in one patient, were low before the challenge test and even lower after the challenge. These findings suggest that the herbal medicine syo-saiko-to may induce acute injury or the hepatocellular pattern with variable cholestasis.