Enisyl-F is a L-Lysine supplement for cats which may help with feline herpes virus infections. Specifically, Enisyl may reduce the frequency and severity of outbreaks. Enisyl provides L-Lysine in an easy to administer treat or oral paste formulation. For the treat formulation, the manufacturer recommends giving 6 treats a day for prevention and up to 12 treats per day for flare-ups. For the oral paste, the manufacturer recommends giving 1-2 pumps (each pump equals 1mL of paste) twice daily for adult cats and giving 1 pump (1mL) twice daily for kittens. These are general guidelines and they do not take place of the recommendations of your pet's veterinarian.