This is an over the counter product - it does not require prescription.
Vetri-Lysine Plus [L-Lysine] is a supplement for cats and is recommended as an aid in the treatment of Feline Herpes Virus. Feline herpes virus [Rhinotracheitis virus] is an upper respiratory virus of cats. The disease is very common among cats, especially in environments where there are multiple cats present, or where new cats are constantly interacting. The virus is spread through the air and replicates in the upper respiratory tract.