Can I Give My Cat Viralys?
Dogs are different
Do not carry this answer over to your dog: for dogs, L-lysine falls under “do not give at home.” Species handle drugs differently, and the cat answer on this page applies to cats only.
About L-lysine
L-lysine is a supplement rather than a drug, which still deserves the same dosing care. You will see it sold as Viralys, and the label strength on the box is what matters for the math, not the brand. Reference data on this page reflects published veterinary sources, not a prescription for your cat.
What to have ready when you call the vet
Whether you are confirming a dose or reporting that your cat already got into something, the call goes faster with four facts ready: your cat's current weight, the exact product name and strength from the label, how much was given or eaten, and roughly when. With those, most clinics can answer in one call.
The safe habit
Confirm any medication decision with your veterinarian, who knows your cat's health history and other medications. VetDose shows published reference data, not prescriptions.