A case is reported in which a several-fold increase in transaminases and γ-GT was detected in an elderly male patient with fatty liver. The patient was regularly taking a mixture of herbal products, used as a laxative, for a number of years, with no alteration of blood chemistry until 6 months before the present observation. However, the composition of the mixture had been modified by the manufacturer in the past 5 months, with addition of boldo leaf extracts. Transaminases promptly returned to normal after withdrawal of the laxative. It is concluded that boldo leaf extracts might be hepatotoxic, at least in elderly patients with fatty liver.