There are many reasons why dogs always scratch, including the following:

< p>1. Parasitic infection: If dogs have external parasites such as fleas, ticks, lice, etc., it will make their bodies very itchy, which will cause scratching behavior.

2. Skin diseases: This condition mainly includes fungal infection, eczema, dermatitis, seborrhea, etc. They will cause the dog to have symptoms such as skin itching, redness, and hair loss.

3. Allergic reaction: This is mainly caused by dogs being allergic to food, certain substances in the environment, pollen, etc. It makes the dog's skin itchy, red and swollen in a short period of time. This is the best time to It is necessary to take the dog to the pet hospital for treatment in time.