I have a 2 yr old male Cornish Rex cat and 2 other older female (8 an 12) cats. The male cat keeps having reoccurring chronic upper respiratory infections. We go to the vet constantly multiple antibiotics by mouth and injections butt the infection comes back within a couple of weeks of getting off the antibiotic. I can no longer afford trips to the vet I am at my wit's end I feed a high quality cat food that does not contain fish because I've heard it can cause allergies. I have done multiple searches on the internet resorted to purchasing antibiotics from a website for him but all to no avail. I've been researching the vitamin C and lysine combination for cats it is important to note here that my cat shows no symptoms of being ill other than sneezing he eats he plays he uses the litter box any other cats show no symptoms of the infection ever. I need help any advice would be great as of today I have started the lysine and vitamin C twice a day 500 milligrams of vitamin C and 1000 of the lysine also I've included a Benadryl in the event this is an allergy thanks for your help.