The primary ingredient in GenF20 Plus is L-Arginine, an essential amino acid that helps to activate the release of HGH from the pituitary gland. Other key ingredients include GABA (gamma-aminobutyric acid), Deer Antler Velvet Extract, Phosphatidyl Choline Complex, Colostrum Powder and Astragalus Root Extract. These ingredients work together to stimulate the pituitary gland and promote healthy HGH production within your body.