Dr. Bennett’s Thoughts On
Allergic Dermatitis
The common forms of allergy include flea allergy, food allergy and inhalant/contact allergy (Atopy). Pets may have 1, 2 or all three of these allergies.
Flea Allergy is common in both dogs and cats. A single flea bite can cause dermatitis in an allergic pet. Treating flea allergy dermatitis may require steroids, antibiotics and anti-itch medications and the fleas must be eliminated from your home and all your pets. Recognize that not all flea medications are equivalent. Fleas may have resistance to some of the older products like Frontline, advantage and even older medications. Most OTC products have questionable usefulness. OTC products may be best used if you have never had a flea problem and your pets are indoor only. But once fleas have found your pets and your home, you will need to treat the home and the pets with better products. I recommend Nexgard, Bravecto, Comfortis or Trifexis, Seresto collars and there are several other products. Please ask your technician for a quality product. Keep in mind flea bites also can transmit diseases and cause severe anemia in pets.
Food Allergy is common in dogs with dermatitis. Cats are less prone to but may also have food allergy dermatitis. Dogs with chronic ear infections, itchy feet or rears or have a generalized dermatitis should go through a food trial. Similarly, cats with ear infections or itchy faces should do a food trial. Food allergy is about the pet being allergic to the protein(s) they are ingesting. Food trials are an 8 to 12 week period where nothing but the trial diet is used. Food trials are a period of time when pets are NOT fed anything else, are not allowed to ingest anything other than the diet being tried. It is to eliminate what they may be allergic to in order to see if their chronic conditions improve. The food they are fed is NOT a cure. It is about avoiding what they are allergic to. The best food to accomplish this is for the food to not have any possible allergen to it. The ideal food for a trial is a hydrolyzed protein diet such as Hill’s z/d or Purina HA or other hydrolyzed protein diets. There are some treats made specifically for these diets also. If you do not wish to use one of the hydrolyzed diets, the best over the counter diet is Purina ProPlan Sensitive Skin and Stomach. It is a salmon and rice diet. Most pets do not have allergy to salmon so this may work for a diet trial or for just longer term use for any sensitive dog.
Atopy is contact and inhalant allergy. Some dogs have allergies worse during certain seasons due to pollens in the environment. But they may also have allergies to year round allergen exposure to things like molds, dust mites, human or other animal dander, etc. My general experience is that the pattern of dermatitis for atopy for this is worse in the armpits, belly and inner legs of the pet. We can reduce some exposure to the allergens if we know what they are but that may not be realistic. We can however offer allergy testing and hyposensitization for your pet. Testing is via blood sent to a lab or through a dermatologist doing a skin allergy test. Hyposensitization is with injections or oral drops. Your pet may need hyposensitization treatment for several years or could be lifelong. Most atopic pets they will live a more comfortable life if on hyposensitization treatment, needing fewer veterinary visits for dermatitis, fewer antibiotics, fewer steroids, fewer immune modulating drugs, fewer other anti-itch medicines and fewer medicated shampoos and topical treatments.
For any cause of dermatitis your pet may benefit from fatty acid supplementation, in particular omega 3 fatty acids. Cats and Small dogs <15 # can have 300-500 mg omega 3 per day, medium dogs 15 – 40# 500 to 1000 mg, large dogs 40-70 # 1000 to 1500 mg and larger dogs 2000 mg per day. There are veterinary formulas and human formulas – even just using fish oil capsules. Read the label. Dose for the omega 3 amount, not the total mg that may be listed. For picky pets you can use krill oil which is not fishy tasting.
