The most common cause of lumpy skin on a cat's neck is miliary dermatitis. This is a type of dermatitis cat's get where they get little crusts form on the skin surface. It's just one of the many ways in which cats are peculiar.
Miliary dermatitis will sometimes involve other parts of the body. Most of the time it starts on the neck and spreads to the rest of the body. When you are patting them the skin feels very rough. If you part the hair and have a closer look you will notice little bumps on the skin like a pimple. There is often a crust on the surface of it and sometimes the crust gets stuck to the hair and may actually be raised up off the surface of the skin.
Causes of miliary dermatitis
There are many possible causes including:
- flea allergy
- food allergy
- environmental allergies
- skin infection
The treatment is generally addressed at treating the underlying cause. Some of the options that may be used include:
- corticosteroids (cortisone)
- allergy exclusion diet
Treatment is needed becuase the skin is very itchy and is often also painful. There are lots of easy options for treating cats such as long-acting injections if it's difficult to medicate your cat.