PUAINTA Hot Spot Spray for Dogs, Upgraded Quantum Silver Skin Spray for Dogs, Itch Relief and Hot Spot Treatment for Dogs, Supports Skin Infections and Irritations for All Animals, 4oz

I could be wrong, but this looks like a hot spot. I had a similar issue with a dog I rescued earlier this year. We went to the vet several times and tried different prescribed shampoos and medications, but nothing really worked. A friend recommended these two products from Amazon after seeing some pictures I sent her, and it cleared up in less than a month Hot Spot Spray & Douxo S3 Pyo Pads Hope this helps!