What to do about flea allergies in cats

Important causes of pruritus other than fleas include:

  1. Insect bites
  2. Atopy (house dust and pollen allergy)
  3. Food intolerance/allergy
  4. Ear mites and other mites
  5. Bacterial infections

Ear mites – Otodectes cynotis

Ear mites are well known as the major cause of otitis externa (ear inflammation) in young cats and in breeding colonies – see common ear problems in cats. However, it is also possible for the mites to wander onto the skin around the head and neck and cause pruritic skin disease at these sites.

As cats sleep curled up, spread of infection (and subsequent dermatitis) to the rump and tail may also occur.

Insect bites

Insects such as wasps and bees can cause stings that lead to dramatic, painful and swollen skin. However, some other insects including fleas, midges, flies and mosquitoes may bite and the reaction to the bite (or the insect saliva) may cause intense irritation and pruritus.

Flying insects generally bite relatively hairless areas such as the bridge of the nose and ears. Notably, mosquitoes own been reported to cause an eosinophilic granuloma-like reaction on the bridge of the nose of some cats (mosquito-bite hypersensitivity).

Atopy (atopic dermatitis; dust and pollen allergy)

Atopy is not well characterised in cats. In humans and dogs, the term is strictly used to describe an inherited predisposition to develop allergic reactions to environmental allergens (such as pollen and home dust). Allergies to pollen and home dust happen in cats, and may be a potential cause of pruritus, but they are hard to diagnose and it is unknown whether there is an inherited component to the disease.

In most cats, atopy is diagnosed by ruling out other potential causes of pruritus, including fleas and other parasites, and food.

Allergy testing can be performed on cats (for example intra-derma skin tests) but the results are rather unreliable. Blood tests are also offered by some laboratories to ‘diagnose’ atopy and the underlying cause of the allergy, but these are less dependable than skin tests, and both untrue positive and untrue negative tests are well recognised.

Atopy is incurable and life-long medication is needed to prevent unacceptable discomfort.

Treatment with essential fatty acids and anti-histamines is successful in only a minority of cases. Numerous cats need long-term corticosteroids or other immunosuppressive drugs such as cyclosporin. If an allergy test has successfully identified the offending allergen, then it is possible to use a ‘hyposensitisation vaccine’ as a therapy – these rarely resolve the disease but in some cases reduce the need for drug therapy.

Other mites

Harvest mites are a recognised cause of skin disease in cats in some areas in tardy summer and autumn – see harvest mite infection in cats. These tiny orange dot sized mites are visible to the naked eye and generally found between the toes and in Henry’s pocket of the ear flap.

In some parts of the world, the mites Noedres cati and Sarcoptes scabiei may be found on cats and may be a cause of intense pruritus.

Food intolerance or allergy

No-one knows the exact mechanisms by which certain foods can make animals and humans itch.

Allergy may be involved, but in some cases, it is possible that the pruritus may result from chemical reactions to the food or to additives and preservatives.

However, it is well recognised that changing the diet to a food that cats own not previously been exposed to can cure some cases of pruritic skin disease. Most of these are probably food allergies but the terms ‘food intolerance’ or ‘food-responsive’ skin disease are sometimes used as a specific diagnosis is often not made.

Cats may need to be fed an alternative diet for a period of 6-8 weeks to law out food-response dermatitis, and the choice of food is significant.

This is not simply switching one brand of cat food for another, as the ingredients are often extremely similar. Your vet will advise you on the most appropriate diet to use – this might be a home-prepared diet, or your vet may propose a special ‘hypoallergenic’ diet for the trial period. Numerous cats also hunt or may be fed by neighbours, which can complicate the trial as it is significant that no other foods are eaten during the trial period.

Bacterial skin infections (pyoderma) and fungal (yeast) infections

Although bacterial skin disease in cats is unusual, it may happen and there are occasional cases of spectacular recovery following antibiotic treatment in pruritic cats.

This is unusual, but more work is needed in this area.

Dermatophytosis (infection with a dermatophyte fungal organism) is not generally pruritic, but skin infection with yeasts (Malassezia) can be a problem in some cats – this is often secondary to allergic skin disease, but the yeasts may also contribute to the pruritus.

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What to do about flea allergies in cats

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Manifestations of feline pruritus

Common manifestations of pruritic skin disease in cats include:

  1. ‘Miliary’ dermatitis – this form of skin disease is characterised by the presence of tiny 2-3 mm diameter crusts throughout the body surface.

    The skin and jacket may also be greasy and own excessive dandruff

  2. Symmetrical hair loss
  3. Overt itching, scratching and self-induced skin damage
  4. Eosinophilic granuloma complicated – see eosinophilic granuloma complicated in cats – this is a variety of skin lesions (indolent ulcer that affects the upper lip, and eosinophilic plagues or eosinophilic granulomas that can affect various areas of the body and also the oral cavity. They are generally associated with allergies. Every of these manifestations of pruritus glance completely diverse, but can every be caused by the same things — in most instances the cause is fleas but other parasites and allergies can be involved.

    Some cats may own more than one manifestation of disease present simultaneously eg, indolent ulcer and symmetrical hair loss.

Like people, our feline friends can develop allergies. This happens when their immune systems become sensitive to substances present in their surroundings. Known as allergens, these irritating substances may not annoy you or other animals in your home, but as your cat’s body tries to get rid of the offending substances, he might show every kinds of symptoms.

Because there is such a wide variety of allergens, cat allergies are generally divided into 3 main categories: flea allergy, environmental allergies (atopic dermatitis), and food allergy.

Flea allergy and environmental allergies – the ones that cause “hay fever” symptoms in humans – are the most common. However, cats often own multiple allergies, so a thorough examination by your veterinarian or veterinary dermatologist is recommended.

Allergic kitties are often extremely itchy and own skin problems associated with allergic dermatitis. They also might exhibit some of these symptoms:

  1. Vomiting or diarrhea
  2. Ear infections
  3. Itchy, runny eyes
  4. Snoring caused by an inflamed throat
  5. Sneezing, coughing, and wheezing – especially if the cat has asthma
  6. Paw chewing or swollen, sensitive paws

There are a variety of allergens that cause these symptoms:

  1. Household cleaning products
  2. Perfumes and colognes
  3. Food
  4. Fleas or flea-control products
  5. Pollen, grass, plants, mold, mildew, and other organic substances
  6. Prescription drugs
  7. Some cat litters

Gastrointestinal symptoms generally accompany a food allergy, so it is significant to avoid feeding your cat food to which he or she has a known allergy.

Also, allergies tend to be more common among outdoor cats because they are exposed to a wider range of potential allergens, especially from plants and organic matter.

If something appears to be making your kitty miserable, the best thing to do is pay your veterinarian a visit. He or she will initially do a finish history and physical exam for your cat to determine the source of the allergies.

If your vet suspects your cat has allergies, he might desire to act out blood tests or experiment with your kitty’s diet to narrow below the cause. Or, if your vet thinks your cat has a skin allergy, your cat might be referred to a veterinary dermatologist.

Treatment & Prevention
The best way to treat your cat’s allergies is to remove the allergens from his or her environment. For instance, if your cat’s allergies are caused by fleas, using veterinarian-recommended flea and tick preventatives can eliminate the cause. If the problem is cat litter, substituting your normal litter for a dust-free alternative could do the trick. In fact, this might assist correct a bigger problem if your cat’s been missing his or her litter box.

When it comes to pollen, fungus, mold, or dust, bathing your cat a couple of times per week can assist alleviate itching.

Your veterinarian can recommend an appropriate shampoo to assist you avoid drying out your cat’s skin.

A diagnosis of food allergies may require you to provide your cat with a prescription diet or even home-cooked meals free of the offending allergens. Your veterinarian will provide recommendations as to the best course of action. It is possible that your cat will need dietary supplements to ensure he gets every the vital nutrients he needs.

Medication is sometimes prescribed for cats in case certain allergens cannot be removed from the environment. Medications include:

  1. Antihistamines as a preventative
  2. Cortisone, steroids or allergy injections for airborne pollens
  3. Flea prevention products

How do allergies affect asthma?
If your cat is allergic to environmental pollutants, it may worsen your cat’s asthma.

What to do about flea allergies in cats

In this case, your vet may prescribe medications that open your cat’s airway for the short-term; endless term solutions include corticosteroids. And here’s a excellent reminder: cigarette smoke is bad for your cat, especially if your cat has asthma.

If you own any questions or concerns, you should always visit or call your veterinarian – they are your best resource to ensure the health and well-being of your pets.

Studies own shown that food allergies overall are the third most common type of feline allergy, outranked in frequency only by allergies to flea bites and inhaled substances.

Although itchy, irritating skin problems are the most common signs of this allergy, an estimated 10 percent to 15 percent of affected cats also exhibit gastrointestinal signs, such as vomiting and diarrhea.

The itching that typically signals the presence of a food allergy is caused by the eruption of little, pale, fluid-filled lumps on a cat’s skin, which form in response to the presence of an allergen, a substance to which the animal’s system is abnormally sensitive.

“The itching eruptions primarily affect the head and neck area,” says Carolyn McDaniel, VMD, a lecturer in clinical sciences at Cornell University’s College of Veterinary Medicine. “They’re not always in that area, but often enough to serve as a clue that the source is a food allergy.”

In themselves, the aggravating lesions do not pose a significant health hazard. But the incessant scratching that they immediate may cause secondary skin wounds and a resulting vulnerability to severe bacterial infection.

In addition, gastrointestinal problems stemming from a food allergy may own far-reaching systemic implications, including food avoidance that can result in health-compromising weight loss.

The most visible signs of a food allergy—the persistent scratching, the emergence of skin lesions, loss of hair, and a general deterioration of the coat—do not develop overnight. Instead, they tend to become evident and intensify over extended periods of time—months or even longer—as the animal’s immune system gradually mounts a defense against certain protein and carbohydrate molecules that are present in most standard cat foods.

“We don’t know why this allergy develops,” says Dr. McDaniel. “A cat of any age can be affected, and it can happen in a cat that has been on the same diet for years.”

When the signs appear, a cat should get immediate veterinary care. If a food allergy is indeed suspected, the specific allergen should be identified and removed from the animal’s diet.

After other potential causes of the skin eruptions, such as flea bites, are ruled out and a food allergy is identified as the probable cause of the clinical signs, the next challenge is to identify what precisely in the cat’s diet is responsible for the problem.

This process will most effectively be carried out at home by the owner’s introduction of what is termed a “novel” diet, which is based on the fact that most feline food allergies are traceable to the protein or carbohydrate content of an affected animal’s normal fare.

The most commonly used protein sources in cat food include beef, pork, lamb, chicken, turkey, and eggs. Since protein is a fundamental component of living cells and is necessary for the proper functioning of an organism, the novel diet must contain protein—but it must be derived from a source to which an affected cat has not been previously exposed, such as venison or kangaroo meat.

Since the same holds true for carbohydrates, the vegetables that are frequently used in cat foods—wheat, barley, and corn, for instance—would be excluded from the novel diet and replaced by, for example, potato.

If a cat consumes nothing but the novel diet and water for a period of at least eight to 10 weeks, it is likely that the allergic signs will gradually vanish. In that case, the owner can assume that the allergen was a component of the previous diet.

And to identify the specific offending allergen, the owner subsequently reintroduces components of the cat’s original diet one by one and watches carefully for the reemergence of allergic symptoms. If the symptoms recur, they will probably do so within a week or two, in which case the owner will own confirmed at least one source of the allergy.

Through repeated systematic testing—and a lot of patience—it is possible for the owner to pinpoint every dietary ingredients to which a cat is allergic.

Therapy, it follows, requires the permanent exclusion of these ingredients from the cat’s diet.

Why is my pet scratching?

There are numerous reasons why pets become itchy. We generally ponder that fleas are the cause, however there are other reasons too. Some pets experience allergies, just love people. Others may own a skin infection that will go away with simple treatments. Thus, ignoring your pet’s skin condition will complicate treatment options and prolong your pet’s discomfort.

‘We often see dogs and cats who own scratched themselves to the point that the skin has been broken.

This can lead to bleeding and infection – which in turn leads to further self trauma  This level of skin damage requires a visit to your local Greencross Vets to ensure a diagnosis and correct treatment are commenced.

Book a vet

Fungal, bacterial, and yeast infections are some common causes of itchy skin that can be simple to treat. So, don’t delay in bringing your pet to the vet to discover out what’s causing them to scratch. Your pet’s quality of life can be affected by uncomfortable itching and scratching, we are here to help!

Skin disorders can be hard to diagnose.

The expertise of a professional veterinarian is needed to ensure safe and effective treatment is started to get your dog back to full health. Some common causes include:

Other causes

Food allergies account for approximately 10 to 15% of every allergic skin diseases in dogs. Diagnosing food allergies can be hard, just love with humans. Chat with your local Greencross Vets team and they can provide advice on how to assist your pet if you suspect a food allergy.

In addition to fleas, another cause of intense scratching could be mites.

These parasites can lead to a skin condition known as ‘sarcoptic mange’. Mange is incredibly uncomfortable, and it is zoonotic, meaning it can be passed from animal to human. Treating the mites that cause mange involves treating your pet and their environment. Enquire our friendly team for advice, we are here to help.

Book a vet

If your pet is scratching their ears, they may own an ear infection. Ear infections can be extremely itchy and painful. If your pet is shaking their head, scratching or rubbing their ears please contact us for advice.

It may or may not be related to an underlying skin allergy

Your local Greencross Vets team will work with you to diagnose your pet’s itch and decide on the best treatment plan. If your dog has been scratching a lot lately, it might be time to discover out why. Together we can ensure your pet is comfortable and happily enjoying life without the itching and scratching.

More commonly, they develop allergies to food products they own eaten for a endless time.

What to do about flea allergies in cats

Food allergies are now estimated to be the second leading cause of allergic dermatitis in cats. The allergy most frequently develops in response to the protein component of the food; for example, beef, pork, chicken, or turkey. Vegetable proteins such as those found in corn or wheat may cause food allergies in some cases. Food allergy may produce any of the clinical signs previously discussed, including itching, digestive disorders, and respiratory distress. Food allergy testing is recommended when the clinical signs own been present for several months, when the cat has a poor response to steroids, or when a extremely young cat itches without other apparent causes of allergy.

Testing is conducted by feeding an elimination or hypoallergenic diet. Because it takes at least eight weeks for every other food products to be removed from the body, the cat must eat the special diet exclusively for a minimum of eight to twelve weeks.

What to do about flea allergies in cats

If a positive response occurs, you will be instructed on how to proceed. If the diet is not fed exclusively, it will not be a meaningful test. This means absolutely no treats, other foods, people foods, or flavored medications during this period. This cannot be overemphasized. Even accidentally providing a tiny quantity of the offending protein can result in invalidating the test.

If your cat’s symptoms improve after the food trail, a presumptive diagnosis of food allergy is made. Exclusively feeding a hypoallergenic diet lifelong is highly successful in treating food allergic skin disease in numerous cats.


Atopic dermatitis  is an allergic reaction to airborne pollens or particles from grass, trees, dust, cleaning products, or mould.

There are numerous treatment options now available for atopic dogs and cats. To diagnose atopy, other causes off allergic dermatitis need to be ruled out. If the time of the year, breed, history, physical examination findings and results of in home skin test are supportive of atopy, a blood or intradermal skin test is then required. Based on the above, your vet will be capable to build a treatment plan moving forward.

Flea allergy dermatitis

Both dogs and cats can be allergic to flea bites, and it might only take one bite from a single flea to cause this allergic reaction.

Dr. Namekata-Wales says, ‘Some dogs are particularly sensitive to flea bites. You may not discover a flea or flea dirt in your dog’s jacket, but one bite could be the cause of their itch.’ Often the itch is extremely intense, especially at the base of their tail. We recommend using effective flea control every year circular, especially if your dog has sensitive skin. Don’t forget to treat every pets in your household for fleas, including cats but remember to use a product that is safe for them.

Type Three: What is inhalant allergy or atopy and how is it treated?

When itching is the primary clinical sign the term “atopic dermatitis” is often used to describe the condition.

It is also referred to as «seasonal allergy» when believed to be related to pollens and grasses.

«Most cats that own an inhalant allergy are allergic to several allergens.»

Cats may be allergic to every of the same inhaled allergens that affect humans. These include tree pollens (cedar, ash, oak, etc.), grass pollens (especially Bermuda grass), weed pollens (ragweed, etc.), molds, mildew, and the common home dust mite.

What to do about flea allergies in cats

Numerous of these allergies happen seasonally, such as ragweed, cedar, and grass pollens. However, others are with us every the time, such as molds, mildew, and home dust mites.

What to do about flea allergies in cats

When humans inhale these allergens, we express the allergy as a respiratory problem. Atopy is also sometimes called «hay fever». The cat’s primary reaction to atopy is severe, generalized itching.

Fleas remain the most common cause of skin disease in cats, although this is not true in every countries (in some regions fleas are rare), and fleas are not the only cause of pruritus (itchy skin) in cats. Where fleas are not the answer, often a much more detailed and meticulous approach is needed to discover the diagnosis.

In some instances in cats, it can be extremely hard to differentiate between skin disease due to pruritus and skin disease induced by other causes.

For example, in humans and dogs, hair loss is almost always hormonal in origin. However, in cats, hormonal skin disease is so rare as to be virtually non-existent. Hair loss in cats is actually almost always caused by excessive self-grooming due to pruritus — but cats may be ‘secret groomers’ and often we may be unaware that the cat is grooming more frequently or more aggressively.

Severe pruritus and eosinophilic 
plaques associated with flea allergy – note matting of the fur with saliva