Melatonin is a hormone (N-acetyl-5-methoxytryptamine) produced mainly at night by the pineal gland. Its secretion is stimulated by darkness and inhibited by light. Melatonin, an indole, is synthesized from tryptophan by serotonin. The suprachiasmatic nuclei (SCN) of the hypothalamus have melatonin receptors, and melatonin can act directly on the NSCs to influence the circadian (sleep) rhythm.IngredientsEach tablet contains :Melatonin 3, 5 or 10 mgDoes not contain :Preservatives, artificial flavors or colors, eggs, corn, yeast, dairy products, sugar, wheat, gluten or soy.