Not really efficaceous: https://www.cochrane.org/CD010095/SKIN_measures-preventing-cold-sores https://www.cochrane.org/CD010095/SKIN_measures-preventing-c... M

Not really efficaceous: https://www.cochrane.org/CD010095/SKIN_measures-preventing-cold-sores https://www.cochrane.org/CD010095/SKIN_measures-preventing-c... My vet said the same (chronic respiratory problems in cats are often caused by feline herpesvirus). The effect on the cat is at best slight.