Imagine a terrible itch somewhere on your nose. It’s difficult to concentrate no matter how hard you try to forget the itch. Just like you, your dog can't resist scratching an itch. Scratching an itch is normal. But, an itch that leads to incessant scratching, licking, biting, and chewing is not normal. It can increase shedding, hair loss, open sores or wounds on skin sores, and other common skin issues in dogs.