Divine Equine is a blend of specific herbs and the amino acid L-Tryptophan. Tryptophan is classified as an 'essential' amino acid. It is classified as such because it is an essential component to equine nutrition and it cannot be synthesized by the body. It is essential to the proper functioning of the equine nervous system. If L-Tryptophan is lacking in the diet, it must be supplemented. The herbs in Divine Equine are those that are known to have a calming or relaxing effect. Administer directly from the syringe onto back of horse's tongue 2-4 hours prior to competition, event or transporting. Contains only test-free ingredients. 34gm syringe. 1 tube per 1,000 lbs.