Hello, my Ollie had surgery last Friday for cherry eye and palate. Things were a little rough the first couple of days. Once he started feeling better Sunday night he developed hives. Took him to the vet first thing Monday morning and they gave him a steriod shot and a shot of benadryl. He was 100% better by evening. We were told to continue the benadryl for 3 days. I gave him his dose this morning but when I got home from work he broke out in hives again! I have not changed his diet or anything in the house. The vet could not give him anymore shots because they told me that it can be damaging to his intestians. The hives went away for about 4 hours and now their back again. He is SOOOOO miserable! HELP...does anyone know what might be causing this or have had the same problem. He is off his meds from surgery. Help!