Could your pet be allergic to fleas?

Studies have shown that there are over 15 different antigens in the saliva of the flea. Each one of these is capable of causing an allergic response in a sensitive cat or dog. Despite recent advances in flea control, flea bite allergies and flea bite dermatitis still continue to be common problems.

Cats and dogs rarely become desensitized to flea bites once they develop an allergy. Cats and dogs that are not allergic to flea bites rarely develop lesions from the bites, but may bite or scratch at the flea when it bites them. There does not appear to be a breed or sex predilection for this allergy.

Flea bite allergy is characterized by being a seasonal allergy that is worse during peak flea times in the summer and fall. Even in temperate areas or in cases with home infestations, the symptoms of flea bite allergies appear to worsen in the summer and fall. Pets that have flea allergies will bite at the base of their tail and scratch frequently. Even a few fleas can cause hours and days of intense itching. Many pets have a characteristic loss or thinning of hair above the base of the tail. In addition, fleas or flea dirt (feces) can be found on the pet the majority of the time. The feces, or flea dirt will dissolve into a red color when moistened; this is because it is primarily digested blood. However, if the pet is bathed or treated regularly, little evidence of fleas may be found. Severely affected pets may itch over their entire bodies, have generalized hair loss, and red inflamed skin.

Dogs and cats with flea allergy dermatitis can have a broad spectrum of symptoms including miliary dermatitis, characterized by crusty papules(small, red, raised skin lesions that follow no specific pattern), symmetrical hair loss(alopecia) and moist dermatitis (hotspots).

Diagnosis can be made usually by visual signs, pattern of hair loss and history in combination with the presence of fleas or flea dirt. A number of topical and oral preparations are available to use as flea control. It is best to use an adulticide, which kills the adult fleas, plus an insect growth regulator (IGR) as well. IGRs help to kill immature forms of the flea, preventing them from developing into biting adults. Talk to your veterinarian about what flea product(s) will work for your pet. In choosing the product, your veterinarian will consider the severity of the flea allergy, the severity of the flea infestation, whether your pet goes outside or to the park, whether there are multiple pets in the household, how easy it is for you to treat your pet, among other topics.

Environmental treatment for fleas involves treating the house, outside areas your pet may frequent, and especially sleeping areas and bedding with an insect growth regulator. IGRs prevent immature forms of fleas from developing, but nothing works against the pupae stage except mechanically removing them by vacuuming. Carbon dioxide from exhaled breath and vibrations from vacuuming can stimulate the pupae to hatch and emerge as adults. Vacuuming with a flea collar, and proper disposal of the cleaner bag can be very beneficial. Pupae can remain in the environment for years before sensing the carbon dioxide and vibration and emerge. Other pets in the home should also be treated also as they could continue to bring fleas into the environment. While there are many methods available today to treat and care for flea allergies and symptoms, an effective flea prevention program is much safer and easier than dealing with a full blown flea infestation.

Common Flea Allergy

Read on to page 3 for information about different flea control products currently available through your veterinarian and the differences between them.

Fleas are not always the cause of itchy skin!

Depending on the type of allergy, your pet may exhibit different symptoms. Although pets occasionally exhibit watery eyes and some sneezing, the most common reaction is scratching. Constant scratching may lead to raised infected welts, open sores, and loss of hair. Ear infections are also common in dogs with allergies.

Pets who are affected by allergies may suffer their entire lives; typically symptoms worsen as they get older. We can help alleviate some of that suffering by knowing the signs of allergies and finding the right type of product relief for the symptoms.

Types of Allergies That Affect Pets

There are four types of allergies that can affect your pet. Allergies caused by things your pet inhales are termed airborne allergies. Common sources are pollens, molds, and dust mites. Allergies that result from flea-bites are referred to as flea allergies or flea-bite dermatitis. Certain allergies occur from items your pet ingests, and are typically called food allergies. Contact allergies or allergic dermatitis are caused by something your pet comes in direct contact with, such as carpet fibers, plastics, and other things. Contact allergies (plastics, carpet fibers, detergents) are far less common than inhalant allergy and flea allergy dermatitis in pets. These allergies may cause:

  • Red itchy bumps or blisters on sparsely-haired areas of the skin and those exposed to the allergen such as the belly, feet, or muzzle
  • Intense scratching
  • Hair loss (in chronic conditions)

Food allergies account for about 10% of all allergies in dogs and cats. Food allergies may show up concurrently with allergies to pollen, dust, etc. Symptoms include:

  • Itching, especially face, feet, trunk, limbs and anal area
  • Ear problems, often yeast-related
  • Skin infections that respond to antibiotics, but then recur as soon as the antibiotic therapy ceases. Occasionally, dogs with true food allergies may have increased bowel movements and soft stool. Food allergies should not be confused with food intolerances, which are not true allergies, and generally cause diarrhea and vomiting.

If you suspect your pet has allergies or chronic skin problems, visit your veterinarian. The type of condition and severity of its symptoms will determine how your veterinarian decides to treat them.

Having trouble deciding on the right flea control?

Controlling fleas on dogs and cats and preventing flea infestation in the home can be a real challenge, particularly during the warmer months of the year.

The most common mistake pet owners make is waiting until their dog or cat is already infested with fleas before trying to control the flea population. Though there are many flea prevention medications which are quite effective, most of the commonly available products for flea control and prevention are much more effective if used preventively.

By the time you start seeing fleas on your dog or cat, you are too late to institute effective flea prevention. 80% of the flea population is in the form of flea eggs, pupae and larvae already present in your home. And these juvenile fleas will continue to mature in your home and infest your dog or cat.

It can take up to eight months for a flea egg to hatch and develop into an adult flea. This means that regardless of the flea product that you use on your dog or cat, it will likely take several months to get rid of the flea infestation in your house if the flea infestation is already well established. And, in the meantime, you will still see adult fleas appearing on your dog or cat as these eggs hatch out.

These new fleas will be effectively killed once they reach your pet, assuming you have treated your pet with an effective flea control product. However, no flea control product applied to a dog or cat will be able to kill flea eggs and larvae pre-existing in the environment because the product will likely not come into contact with these eggs and larvae.

The best way to control fleas on your dog or cat is to start treating for them preventively, before you see any fleas on your dog or cat. Stop them before they get started and you will not have to worry about flea infestations. If you are not currently using a flea prevention product on your dog or cat, you should start doing so immediately. Beginning flea control measures now for your dog or cat will save you a lot of aggravation and expense in the summertime when fleas are rampant.

Do not stop giving the flea prevention medication in the winter. Many people believe that fleas cannot breed and reproduce in the winter. This is not always true. Under certain conditions, fleas are able to actively reproduce, even in the middle of winter. Crawl spaces under your home, dog houses and other sheltered areas provide adequate conditions to allow fleas to reproduce all winter long. Fleas can also breed and reproduce very well inside your home all winter long.

There are many good flea prevention products available. These are the ones we carry and usually recommend.

  • Frontline Plus (Fipronil & Methoprene)
    Fipronil is the chemical that kills the adult biting flea, tick, lice and sarcoptic mite. Methoprene is the growth regulator. This is the product that can last for up to 3 months. This kills the flea larva, egg and prevents the pupa from developing. The catch is that if the parasites are not on the pet, the chemicals will not work on the animal. Safe for puppies & kittens 8 weeks and older. Application every 3 wks is recommended for dogs and cats who are allergic to fleas.
  • Sentinel (Milbemycin oxime/lufenuron)
    Sentinel acts as a heartworm preventative as well as intestinal parasite prevention and controlling flea populations. Sentinel does not kill the fleas but acts as a birth control making the flea eggs sterile and thus preventing 80% of the flea population from developing into adult fleas. This product is an oral medication given once a month for dogs only and is safe for puppies over 4 wks old and weighing over 2lbs.
  • Revolution (Selamectin)
    Selamectin is absorbed into the skin and goes into the bloodstream. This product selectively filters through the skin to be a flea preventative. Selamectin also kills heartworms in selective stages of growth. Revolution is available in both adult sizes and kitten/puppy sizes. Revolution is labeled for killing adult fleas, flea eggs, heartworms, ear mites, hookworms and roundworms in cats, and adult fleas, flea eggs, hookworms, ear mites, sarcoptic mites and American dog ticks in dogs. This product is absorbed into the skin so it does not wash off. It is typically applied once a month, for allergic dogs and cats, application every 3 weeks is recommended.
  • Comfortis (Spinosad)
    Spinosad is an oral medication for dogs only, over the age of 14 weeks. Spinosad effects the motor neurons of the adult fleas causing hyperexitation, paralysis and death. When given to your dog each month, Comfortis tablets kill adult fleas before they are able to lay their eggs. Because this is an oral medication, it may be a good choice for dogs who are avid swimmers or if you or your dog don’t like the feeling of the greasy topical medications.
  • Capstar (nitenpyram)
    Nitenpyram is an oral medication that provides fast flea relief and starts working within 30 minutes. A single dose will kill the adult fleas currently on your pet-you will literally see fleas falling off your pet. It is also remarkably safe so if your pet gets reinfested, you can give another dose as often as once per day. CAPSTAR is safe for use in kittens and puppies over 4 wks old and weighing over 2lbs, and can even be used in pregnant or nursing pets. CAPSTAR also works well in conjunction with Sentinel.

There are many products on the market. Consult your veterinarian to determine which product is best suited for your pet.