A method of treating a human subject in need of melatonin therapy comprises administering to a human subject a composition comprising melatonin dispersed in a polymer matrix adapted to cover the melatonin in a melatonin solubility enhancing pH environment after ingestion and to maintain the melatonin solubility enhancing pH environment when said composition is present in said subjects intestines so that an effective amount of melatonin is released into the subjects intestines.
