Your sweet Shih Tzu has taken over your heart, so don't let him be taken over by something quite different -- fleas -- especially if he's allergic to them. Flea allergy dermatitis, or flea bite hypersensitivity, is the most common allergy in dogs and can make your little Tzu miserable.
Allergic to What?
When a flea bites your Shih Tzu, it injects saliva to prevent the blood from clotting as it feeds. An allergy-free dog may scratch at the annoying bite, but in a flea-sensitive dog, that single bite can cause intense, near-constant itching. Animals with environmental allergies are thought to be more likely to develop flea allergies. This is bad news for Shih Tzu owners because the Merck Veterinary Manual mentions that the breed can be predisposed to atopy, an allergy to airborne allergens.
Signs of the Problem
If your Shih Tzu has a flea allergy, the pruritus, or itchiness, he experiences can be severe and affect his entire body, though his lower back, rump, abdomen and inner thighs are areas that often show the most irritation. Your dog might seem restless and uncomfortable, spending much of his time scratching, rubbing, licking and chewing at himself. Surprisingly, when you check him for fleas, you might find little sign of them. A dog with a flea allergy is often so itchy that he'll groom himself excessively, eliminating most evidence of the little bloodsuckers. If you keep your Tzu in full coat, there will likely be a great deal of fur damage, as well as mats and tangles, from the scratching and chewing.
If you don't take care of your Shih Tzu's flea allergy dermatitis, you may notice areas of fur stained brown from his licking and chewing. You may also start to see moist, inflamed areas of skin -- and even hair loss -- on your little dog. Keep in mind that FAD often leads to secondary infections. Your Tzu's immune system can be weakened by the allergy and the stress of pruritus, allowing the bacteria or yeast normally found on his skin to grow beyond its usual low numbers and cause a skin infection.
This can be a particular concern for owners of Shih Tzus because the breed is believed to be at increased risk for yeast skin infections in the first place. As well as being itchy, bacterial infections often show as small bumps on the skin, while yeast skin infections usually cause an unpleasant odor and greasiness. Either infection is easily cleared with medicine from your vet, but the flea allergy that led to it will still need to be addressed.
Your vet has several options when diagnosing flea allergy dermatitis. She may look at your Tzu's history and symptoms, check for evidence of fleas and rule out other possible causes for his itching. She will probably advise you to try ridding the little dog and his environment of any and all fleas and see if his symptoms improve. She may perform allergy tests, through either skin pricks or blood tests using flea-specific salivary antigens.
How to Help
Flea preventatives are the simplest way to tackle a flea allergy in Shih Tzus. Topical adult flea preventative is usually a better choice than an oral product because it kills adult fleas before they bite, keeping your dog from being exposed to their saliva. If there's heavy infestation, you need to treat indoor and outdoor areas for fleas as well. Your vet might prescribe antihistamines and corticosteroids, which can relieve your pup's intense itching, but only while he takes them. They won't solve the allergy problem. Finally, hyposensitization, or allergy shots, provide another option, though the effectiveness of whole flea extracts currently available is debatable. Talk with your vet and make sure you understand the risks and benefits of any treatment she suggests.
- PetPlace.com: Flea Allergy Dermatitis in Dogs
- University of Illinois at Urbana-Champaign, College of Veterinary Medicine: Stop Itching!
- University of Illinois at Urbana-Champaign, College of Veterinary Medicine: Itchy Dogs
- VSI (Veterinary Specialists Inc.): Malassezia (Yeast) Dermatitis
- VetInfo: Diagnosing Dog's Allergies to Fleas with Serologic Allergy Testing
- University of Illinois at Urbana-Champaign, College of Veterinary Medicine: Fleas Can Make Your Pet Very, Very Itchy
- American Shih Tzu Club: Canine Skin Problems
- Jupiterimages/Photos.com/Getty Images