Parasites like fleas, ticks, and mites can cause skin irritation and inflammation. If dogs scratch and chew the area relentlessly, it can lead to crusty scabs.

Bacterial skin infections, like pyoderma, can cause a dog’s skin to become inflamed and infected, leading to pustules. Eventually, crusty scabs form over the infected area as a protective mechanism.

Allergic dermatitis often leads to excessive itching, scratching, and paw chewing, which can result in hair loss and crusty scabs on dogs.

A lack of essential nutrients can impact skin health, leading to dryness, flakiness, and scabs on your dog’s skin.

Yeast overgrowth on the skin can also cause redness, itching, and crusty scabs on dogs. These infections are commonly seen in areas with folds like the face, paws, and ears.