My 7 year old cat for the past 3 years one time per year chews hair off her belly and chews sores. Then she licks and irritates them to a dry red patch. The vet has given her steroid spray and some antibiotics in the past. This clears it up within 1-2 weeks but now she is doing it about every 3-4 months and the bills are really adding up. Is there anything over the counter I can try --some cream or something I can order cheaply on the internet?