rash

My cat who is indoors only has developed this rash that is pictured. There has been no changes in her daily activity or food. It doesnt seem to bother her but what can I give her to make it go away?

I'm not a vet, but that looks like ringworm to me. You need to take her to the vet and get anti fungal meds for her. She might need medicated washes too (I've never dealt with it in a cat so I'm not certain of the process).

Even if I'm wrong, that rash looks nasty and needs to be seen by a vet anyway.