L-TRYPTOPHAN is an essential amino acid that serves as a precursor for the sleep hormone melatonin as well as for niacin and serotonin. Serotonin is an important neurotransmitter in the central nervous system that has a calming effect and helps modulates mood, sleep, and metabolism. L-Tryptophan is the least abundant amino acid in the American diet. Even a person on a high protein diet generally gets less than 1.5 grams a day. Supplementary L-Tryptophan may provide nutritional support for restful sleep and a positive moodSuggested Use Take one capsule daily, typically at bedtime, or more, as directed by a health care professional.Serving Size:1 Capsule Servings Per Container: 90 Amount Per Serving Ajinomoto TryptoPure (L-Tryptophan) 500 mg Other Ingredients: hypromellose (vegetable capsule), vegetable lubricant. Warnings If you are pregnant, breastfeeding, or are taking medications such as SSRIs or MAOIs consult your health care professional before using this product. May cause drowsiness. Tamper evident band around cap and seal on bottle. Do not use if either seal is broken or missing. Keep out of reach of children.