L-lysine Pro supports immune system function, eye and respiratory health. As an important component of many proteins, l-lysine supports antibody, hormone and enzyme production. It also promotes healthy growth and development by supporting the production of collagen. L-lysine and the amino acid l-arginine compete for the same receptors in the body. L-arginine is required for the replication of the herpes virus. With twice the lysine of vetri lysine plus, and the addition of dmg, l-lysine Pro offers advanced support for cats.