Here is a list of itchy skin diseases other than a current infestation of cat fleas. One of them may apply to your cat. However, there is no substitute for taking your cat to a good veterinarian. Unless you are very competent, I would not try and self-diagnose your cat’s itchy skin unless it is pretty obvious such as fleas jumping out of his fur!
Allergic contact dermatitis; this is similar to contact dermatitis. The rash may be wider than on the area of contact. To suffer from this disease a cat has to be repeatedly exposed and/or continuously exposed to an allergen.
Chiggers: this is a tropical flea, the female of which burrows and lays eggs beneath the host’s skin causing painful sores. It causes itching and severe skin irritation between the toes and around the ears and mouth. You might be able to see the larvae which are hardly visible and are read, orange or yellow.
Contact dermatitis: this causes an inflamed skin with bumps, which is itchy and red at the site of contact with an irritant such as paint, detergent or a chemical. It can sometimes be caused by plastic or rubber food dishes. There may be hair loss and a scaly skin.
Ear mites (ododectes): these are nasty little parasites which cause intense irritation in the ear canal. They sometimes migrate out of the ear canal onto the body. Your cat will scratch at her ears, head tilt and shake her head to try and alleviate the itching. An inspection by a veterinarian will reveal excessive brown, waxy or purulent material in the ear canals.
Feline miliary dermatitis: this is often a flea bite allergy. ‘Miliary’ comes from the word ‘milium’ which is Latin for millet (seeds). The crusty lesions of the skin look like millet seeds. There are small bumps and crusts around the head, back and neck which can be felt beneath the fur. It may be complicated by pyoderma.
Flea allergy dermatitis: over the inner thighs, rear legs, back and the base of the tail there will be red, itchy pimple-like bumps. After you have killed the fleas and your cat is flea-free, the scratching will continue.
Food allergy dermatitis: there may be swelling of eyelids combined with severe itching over the head, neck and back. Or it may present as reddened ears. There may be hair loss and oozing sores because the cat scratches and bites herself.
Inhalant allergy a.k.a. atopic dermatitis: this is similar in symptoms to feline miliary dermatitis and the maybe symmetrical hair loss over the body.
Lice: Lice can live on the skin of a cat and feed on it. They are 2 mm long insects or white grains of sandy material, which are the eggs called nits, attached to the hair. They sometimes infest cats with matted coats living in poor conditions. There may be hair loss where the hair has been rubbed off.
Maggots (myiasis): This is a fly larva. It is soft bodied. The fly lays them in the fur, or in an open wound. My experience tells me that if a cat is ill cat is very static for long periods of time outside the home, they may acquire maggots. I don’t think they always cause irritation though.
Scabies (sarcoptic mange): This presents as thick grey to yellow crusts with the hair rubbed off. It causes intense itching around the edges of the ears, neck, face and head.
Ticks: a parasite which is quite large, relatively, when bloated with blood or quite small before feeding. They attached to the skin. They are picked up in long grass. They might be walking slowly through a cat’s fur. They are often found along the back, around the ears and between the toes.
Walking dandruff (cheyletiella mange): Itching may be mildly caused by large amounts of dry scaly, flaky skin over the neck, sides and back.
The list might not be comprehensive. Please do your own research and consult with a good vet if needs be. Itchiness is distressing to very distressing for cats so prompt action is desirable.
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