Sometimes flea infestations can be much worse than a simple itch. Flea Allergy Dermatitis (FAD) is an allergic skin disease that is caused by fleas. It is the most common pruritic (itchy) skin disease in the dog. Apart from being intensely uncomfortable, FAD can lead to severe complications such as deep skin infections, hair loss and scarring.

FAD is caused by an allergy to the saliva of the cat flea, Ctenocephalides felis. Unfortunately for us Aussies, this happens to be the most commonly encountered flea in Australia. This is also the case in the warmer parts of America. Long coated breeds seem to be the most commonly affected. FAD is mostly seen in young adult dogs, but it can also develop in older dogs, often causing much more severe disease.

The most obvious sign of FAD is severe itchiness, leading to self trauma. This itchiness is independent of the number of fleas on your dog. This means that your dog will be just as itchy from five fleas as from fifty. In comparison, dogs without flea allergy dermatitis will show signs of itchiness directly in proportion to the number of fleas that they are carrying.

Dogs with FAD have a common pattern of redness, papules, hair loss and crusting over the base of the tail. This will eventually spread to the top of the back, perineum, thighs and abdomen if left unchecked. After a while, dogs with FAD may develop bacterial or yeast infections in these areas due to the trauma.

This is probably the biggest misunderstanding about Flea Allergy Dermatitis. Logically, you would think that if your dog has flea allergies, you should be able to find fleas, right? Wrong!

Strangely enough, finding fleas on a dog with flea allergy dermatitis is often quite difficult. These guys are extra itchy, so they tend to groom themselves more often than unaffected dogs, meaning they are more effective at removing fleas themselves. Not to mention that fleas are hard to find anyway, with only 5-15% of fleas on the animal able to be found at the best of times. So don’t make the mistake of thinking that your dog doesn’t have fleas just because you can’t find any!

If you think your dog might have this disease, you really need to visit a vet. Flea allergy dermatitis is a big deal, and delaying treatment often means that the problem gets worse and worse, and more expensive to fix. Not to mention the serious discomfort your pet will feel being itchy all the time.

Your local veterinarian will be able to examine your animal and prescribe the right medication. This will generally involve a strict flea control program, anti-inflammatory medication and possible antibiotics, antifungals or shampoos, depending on the type and severity of disease.

Flea Allergy Dermatitis is nasty business, and is a problem best avoided rather than treated. The only way to ensure your dog will not get FAD again is to maintain a strict regimen of flea control all year round. Even one bite could possibly cause a relapse of disease, so you have to be especially vigilant.