Douglas Laboratories. Appetite Support: Serotonin, an important neurotransmitter, supports satiety signals in the brain, naturally regulating food intake.* Sleep Support: As a precursor of melatonin, serotonin supports healthy sleep patterns.* Vitamins/Minerals/Amino Acids: Our vitamins/minerals and amino acid formulas are developed to provide beneficial support in filling nutrient gaps.* Our uncompromising operational practices at our state-of-the-art manufacturing facilities surpass GMP standards and manufacturing regulations. All of our products are GMO-free. For 65 years, Douglas Laboratories has been dedicated to meeting the needs of healthcare professionals. As a globally recognized leader in the development of innovative, science-based nutritional supplements, we strive to help healthcare professionals and their patients push their potential for healthy living, today and in the future.*