Possible Side Effects of Flea Bites in Dogs

by Adrienne Farricelli Google
    Don't let Pongo run in circles all day.

    Don't let Pongo run in circles all day.

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    If your dog is scratching, chewing and chasing his tail, you may suspect a flea problem. Fleas can bring much more than a sudden bout of itching and scratching. Side effects from flea bites are not uncommon and may lead to annoying dermatological problems requiring the intervention of your vet.

    Flea Allergy Dermatitis

    In this case, the allergy isn't directly triggered by exposure to fleas, it's caused by exposure to the fleas' saliva. As the flea pierces the dog's skin to enjoy a blood meal, it introduces several potential allergens including amino acids, aromatic compounds, polypeptides and phosphorus. When hypersensitivity to these compounds takes place, the skin becomes inflamed and the dog may develop intense itching and scratching, scabs and hair loss. Your dog doesn't need to be infested with a load of these pesky critters to be symptomatic.

    Skin Infections

    When the skin is inflamed and vulnerable because of flea allergy dermatitis, an opportunistic infection may set in. In this case, the inflamed skin becomes victim of tissue damage, which creates the perfect breeding ground for harmful bacteria such as Staphylococcus intermedius and Malassezia pachydermatis. Soon, the skin becomes the victim of a secondary bacterial or fungal infection, which triggers more scratching and chewing leading to a vicious cycle that can compound the allergic reaction.

    Neurogenic Dermatitis

    In some cases, some dogs may develop behavioral problems as a result of flea bite dermatitis. This condition is known as neurogenic dermatitis and is caused by a dog's obsessive desire to chew and lick himself. Often, it starts from a tiny abrasion, which captivates the dog's interest. As Fido continues traumatizing the area, it quickly evolves into a visible wound, which may further mutate into scarred tissue and even permanent skin damage.


    Sometimes, as Fido persists in chewing and licking at his flea bites, he may accidentally ingest one or more fleas, which are the intermediate hosts for tapeworms. Not all fleas are infected with tapeworms, but all it takes is for Fido to ingest the tapeworm infected flea to complete this pesky parasite's life cycle and end up with a tapeworm infestation. Luckily, stringent flea control along with a dewormer purposely crafted to kill tapeworms, will solve the problem.


    At times, dogs are so heavily infested with fleas, their body cannot cope. When too many fleas feast on Fido, a low red blood count may result potentially leading to debilitating anemia. The most vulnerable victims are outdoor puppies who are too young to effectively groom themselves. Fortunately, these young pups can be helped by blood transfusions and a good flea control program.

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    About the Author

    Adrienne Farricelli has been a writer since 2005, serving as an editor, steward and writer for several online publications. She brings expertise in canine topics, previously working with the American Animal Hospital Association and receiving certification as a dog trainer from the Certification Council for Professional Dog Trainers. Farricelli offers reward-based training and behavior consults at Rover's Ranch Home Boarding and Training.

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