Aloe, being used widely as a health food and also as a traditional folk remedy for burns and constipation, contains quinone derivatives particularly in its skin. Thus, we have investigated the effect of extracts of Aloe on ethanol metabolism. The dried powder of water extract of skinned Aloe (300 mg/kg body weight given to rats by oral administration at 30 min prior to oral administration of ethanol given at a dose of 4 gm/kg) and the freeze-dried Aloe gel commercial product (600 mg/kg) which was prepared after selective elimination of quinones were found not to increase the ethanol metabolism rate in vivo. This result suggested that quinones, missing from the above preparations, might be responsible for enhancing ethanol metabolism rate.