L-lysine for cats

Sold as Viralys, generic. Published reference range, cited. Enter your cat's weight below.

Reference tool, not medical advice. Always confirm with your veterinarian.
Your cat's weight

Published dose range

Published guidance for cats: 250-500 mg per cat, every 12h.

Source: Veterinary Partner (VIN) →
Traditionally used for feline herpesvirus flare-ups; evidence is mixed, recent studies question benefit. Safe, but manage expectations.

If you think you overdosed

Call the Pet Poison Helpline: 855-764-7661 or ASPCA Poison Control: 888-426-4435. Both are staffed 24/7 by veterinary toxicologists.

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