Compositions for increasing the rate of metabolism of alcohol in a human and preventing the symptoms of a hangover comprising amino acids of one or both of L-arginine or L-citrulline； one or more of L-glutamine, L-glutamic acid, L-glutamine or theanine； and one or both of L-tyrosine or L-phenylalanine. The compositions may also contain other ingredients, such as B vitamins and plant extracts.
