Did you know that L-lysine is used for eye and upper respiratory health in cats? When I was in rescue, it was one of the first things we gave kitties that came in with upper respiratory. It was only recently that I discovered that it has many benefits for humans too. It's an essential amino acid that is used for treating cold sores and herpes; may be helpful in strengthening bones and the immune system, reducing anxiety, heart health and reducing diabetes complications. It is necessary for production of proteins.
*Side affects, particularly if taking too much, may include GI tract upset, kidney or liver disorders, or gallstones.
I've been giving my kitties L-lysine for a long time. Now I take it too.