Most people associate scratching in cats with fleas. While fleas are often the cause of this, there are many other possible causes of scratching in cats. If your cat is scratching, it should be checked out by a veterinarian. Almost all cases of scratching are not serious, however there is almost always a reason why your cat is scratching which should be investigated and treated. Any scratching has the potential to damage the skin, which can lead to a bacterial infection.
The most common cause of itching in cats is due to fleas. They are most abundant in the summer months, although in tropical areas may be found all year around. Signs of cat fleas include seeing small, black insects in the coat, grit like appearance in the cat's bedding and scratching.
If your cat has fleas, you will have to treat both the cat and your home. Your veterinarian will be able to advise on the best product to use on your cat. There are many excellent products on the market for cats, many of which are applied to the back of the neck. The environment will either need to be treated with a flea bomb or a pest controller, along with some thorough washing and vacuuming. For further information on cat, fleas read here.
Flea allergy dermatitis:
While the odd flea on most cats won't bother them too much, some cats will be hypersensitive to them. This is known as Flea Allergy Dermatitis (also known as flea bite hypersensitivity).
As the name suggests, it is caused by an allergic reaction to a flea bite. There are 15 known allergens in flea saliva, each one is capable of causing an allergic reaction in the cat. Just one bite from a flea is enough to trigger an allergic reaction in your cat. FAD is one of the major causes of miliary dermatitis in cats.
Some symptoms include frequent scratching and biting of the fur, especially on the back and the base of their tail. Other symptoms of flea allergy dermatitis include raised bumps (papules) or scabs on the skin and thinning fur in the affected area.
Your veterinarian will be able to diagnose flea allergy dermatitis. This can be done visually. Signs of fleas on your cat are a good indicator. However, extremely sensitive cats will have few if any fleas on them. This is due to excessive self-grooming. In such cases, to get a definite diagnosis that your cat is in fact allergic to flea bites and not something else then an intradermal skin testing is required.
Treatment for flea allergy dermatitis includes:
- Eliminating fleas from your cat and environment, and preventing re-infestation of fleas.
- Treating secondary skin infections caused by excessive biting and scratching of the skin. This may involve a course of antibiotics, medicated shampoo and or a topical medication.
- Antihistamines or steroids may be prescribed by your veterinarian to control inflammation and reduce itching.
- Hyposensitisation (desensitisation). This involves injecting minute amounts of flea antigen into the cat in the hope that it will re-programme the immune system so it's not hypersensitive to flea antigen.
Mites are tiny members of the arachnid (spider) family. There are several types of mites in cats including Notoedric Mange, Cheyletiellosis (walking dandruff), Lynxacariasis, Trombiculidiasis and Otodectic Mange (ear mites). Most of these are fairly rare in the cat so I won't go into detail.
Ear mites (Otodectes cyanosis): Although the name would suggest otherwise, ear mites can live on any part of the body although they generally live in the ears of cats. They are the most common cause of otitis externa (inflammation of the outer ear canal) in cats.
Not all cats will display symptoms of ear mites but often they will scratch at their ears and or shake their heads. Other symptoms may include reddish/brown discharge in the ear, bleeding from the ear, coffee-grounds like appearance in the ear, scratch marks, odour.
Treatment depends on how severe the problem is. Removal of the exudates from the ear by instilling a few drops of mineral oil and gently massaging the base of the ear. This will loosen the exudate, which will make it easy to remove.
Notoedric Mange (feline scabies) is a highly contagious, intensely itchy skin disease, caused by the mite Notoedres cati. These mites are closely related to the Sarcoptic mange, which causes mange in dogs.
The first sign of notoedric mange is usually intense pruritus (itching) along with hair loss and a thick/crusty and scabby appearance to the skin, especially on the tip of the ears. It then progresses to the face and neck, and if untreated can progress to other parts of the body.
Scratching the affected areas causes the skin to become raw, red and inflamed, which can cause potentially dangerous secondary bacterial infections.
Diagnosis is made by taking a scraping of the cat's crusty skin examine it under a microscope for the presence of mites or mite eggs.
- Semi and longhaired cats may need to be clipped. Cleansing of the area to soften thick crusts, followed by a weekly lime sulfur dip.
- Amitraz has been shown to be another successful dip, this product hasn't been approved for use on cats though
- Ivermectin. This is given by injection. It hasn't been approved for use in cats, although reports are that it is safe. According to the Merck website, it has been known to cause death in kittens.
- Revolution: This product is typically a flea and worm product but has shown to be effective on notoedric mange.
Cheyletiellosis: Also known as walking dandruff, cheyletiellosis is a highly contagious skin disease cause by the Cheyletiellosis mite. Cats are most commonly infected with Cheyletiella blakei. Young cats are more often infected although cats of any age can have these mites.
Symptoms include pruritus (itching), excessive scaling/dandruff, crusting along the back.
Cheyletiellosis is diagnosed by flea combings, skin scrapings, fecal flotation or acetate tape preparations.
Treatment may include lime sulfur or pyrethrin dips and or Ivermectin.
The word allergy means altered working and just like humans, cats can have allergies too. However allergies in cats more commonly manifest as skin disorders.
The purpose of the immune system is to keep infectious microorganisms, such as certain bacteria, viruses, and fungi, out of the body, and to destroy any infectious microorganisms that do invade the body. Allergies are caused by an inappropriate response to a substance which would usually be considered harmless. In an allergic animal, the immune system overreacts to the substance and mounts an immune response against it.
In cats, there are four types of allergies; insect (most often caused by fleas, but occasionally mosquito bites can cause an allergic reaction), food, contact, and inhalant.
All the above causes have different symptoms, most of which are already covered in specific articles but scratching is often seen in the case of allergies.
Feline miliary dermatitis:
Miliary dermatitis (also known as miliary eczema, papula crusting dermatitis or scabby cat disease) isn't a specific disease but a disease complex. It is characterized by a red and crusty rash around the head, neck, and back, often with intense itching.
There are several causes of miliary dermatitis including flea bite hypersensitivity, Allergies; food intolerance, inhalant allergy, food allergy, bacterial infections, mites, mange, ringworm, yeast infections, immune-mediated diseases, drug hypersensitivity, poor diet and hormonal/endocrine disorder.
Symptoms include red, crusty bumps, especially around the head, neck and back, often with intense itching, hair loss, scratching.
Treatment of feline miliary dermatitis depends on the cause of the problem.
- If it is fleas, then removal of the fleas from the cat and environment should cure the problem. Strict flea control will need to be performed routinely to ensure the miliary dermatitis doesn't recur.
- The same goes for mites, mange or fungal or yeast infections. Treat the cause and miliary dermatitis should go away.
- If intestinal parasites are found to be the cause, treatment with the appropriate medication to eliminate them.
- A hypoallergenic diet may be tried if parasites, yeast infections, fungal infections etc., are ruled out.
- Antibiotics for secondary skin infections, if required.
- Shampoos may be recommended to relieve itching and inflammation.
- Other possible treatment options include fatty acids, antihistamines, and corticosteroids.
Ringworm is the most common fungal skin infection seen in cats. Contrary to the name, ringworm is caused by a microscopic group of parasitic fungal organisms known as dermatophytes (which means "plants that live on the skin"). Ringworm invades the dead, outer layers of the skin, claws, and hair.
The most recognised sign your cat is infected with ringworm is circular patches of hair loss, especially around the head and limbs (although it can occur on other parts of the body also). Other signs are grey, patchy areas of baldness, with or without redness and itching, seborrhea sicca (a type of dandruff), dry/flaky skin, onychomycosis (infection of the claw and claw bed).
Insect bite or sting:
Ants, mosquitoes, bees, wasps and many other insects all have the potential to bite your cat which can cause an allergic reaction. This is usually self limiting, unless your cat develops an allergy.
Treatment involves using an ice compress to relieve itching. Your veterinarian may also recommend an antihistamine.
This yeast lives on the skin of cats and ear canal of cats in low numbers and usually causes no problems. However in some cats, the yeast begins to grow to the point where it causes disease. This is usually the result of immunosuppression (such as a cat with feline immunodeficiency virus or feline leukemia virus), long term antibiotic use, allergies which damage the skin, endocrine disorders and certain tumours. Symptoms of malassazia include itching, hair loss, greasy lesions, unpleasant odour, swelling of the affected area, and waxy build up of the ears.
Treatment includes addressing the underlying cause, anti-fungal sprays or shampoos, and medications such as Itraconzole for severe cases.
A skin disorder caused by an over-production of sebum, an oily substance produced by the sebaceous glands to keep the skin lubricated. It may be primary, which is an inherited condition, or secondary, as a result of an underlying disease such as parasites or Cushing's syndrome. Symptoms include itching, patches of greasy scales, and in some cases secondary bacterial infection.
Treatment includes finding and treating the underlying cause, if one is found and medicated antiseborrheic shampoos. Fatty acid supplements may also be recommended.
Adverse reaction to flea products:
While rare, some cats can have an adverse reaction to spot-on flea products or flea collars. Symptoms can range from mild itching to severe chemical burns.
Treatment involves switching to another flea product.
Inflammation or infection of the hair follicles characterised by red lumps on your cat's skin. The head, chin, neck and base of the tail are most commonly affected. Most cases of folliculitis are due to damage to the skin, caused by an underlying condition, such as feline acne.
Treatment involves finding and addressing the underlying cause as well as medicated shampoos, antibiotics and in some cases topical glucorticoids to reduce inflammation and itching.