Dietary supplement. Source Naturals timed release melatonin is formulated to allow for a gradual release of the active ingredients during an approximate six hour period. This provides the body with a more even absorption of melatonin. Suitable for vegetarians and hypoallergenic: contains no yeast, dairy, egg, gluten, corn or wheat. Contains no sugar, starch, salt, preservatives, or artificial color, flavor or fragrance.