L-lysine
Human Medication
L-lysine is an amino acid supplement that may be beneficial for dogs with certain viral infections, especially feline herpes virus in cats. While it is generally safe and well-tolerated, the efficacy in dogs is not well-established. Consult your veterinarian before giving L-lysine to your dog, as they can advise on the appropriate dose and whether it is likely to be helpful for your dog's specific condition. Overdose is unlikely to cause harm, but very high doses may cause gastrointestinal upset.