Food Allergy?

Jorin has a sore on his stomach. I'm not sure what it is, but it doesn't seem to be getting better. He's going to the vet tomorrow, but I thought I'd see if anyone on here has any ideas what it could be? I'm thinking he may be allergic to the new food. It doesn't seem to be tender or itchy.

My male cat Peppurr had that same problem. It looked just like that. I took him to the vet and they told me it was either because of fleas or stress. Peppurr used to bite at his belly when he was cleaning himself. Eventually he had big red sores. Check for fleas. What kind of food is he on?

he's currently on Authority kitten formula. He does have a few fleas nothing like when we first got them though.They're both on Advantage. It doesn't appear to be tender, like he'd been digging at it. I also haven't seen him licking it or anything. I noticed the sore shortly after I switched them to the premium food from the "junk" food (Friskie's Kitten or Purina Kitten Chow).

If you shine a black light on it and it glows green it may be Ringworm. It looks like a scabby sore that gets bigger and the hair falls out. I heard you can treat it with Lambasil ointment. (Athletes foot medication.)Let us know what the vet says1

Took him in, wasn't ringworm. He thinks it may just be a scrape or possibly an allergy. He gave me some stuff called Tresaderm to put on it twice a day.