Take him to the clinic
It could be an allergy that can be caused by many things such as his food or other items in the household bothering him. It could also be a hot spot. Best thing to do it to take him to the clinic and have it checked out to make sure that there aren't any underlying causes. There are many natural remedies for itching. See the vet and then determine the best course of action for your dog. It doesn't always have to be by prescription.
Take him to the veterinary it could be anything like that u can help him to get well
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