Dog and Cat food hypersensitivity is an adverse reaction to a food or food additive. It can occur at any age, from recently weaned puppies to elderly dogs that have been eating the same food for years. Approximately 30% of dogs diagnosed with food allergy are younger than 1 year of age. It is common in dogs. Dog food hypersensitivity is characterized by nonseasonal itching that may or may not respond to steroid treatment. This itching, scratching or licking may be regional or generalized and usually involves the paws, ears, inguinal or axillary areas, face, neck and perineum (anal area). Affected skin is often red and inflammed, and papular rash may be present. Secondary bacterial or yeast infection, and Otitis externa (ear infection) are common. Other symptoms that may be seen are acral lick dermatitis, oily, smelly skin or ears dermatitis. Some dogs are minimally itchy, with only symptom being recurrent infection with Pyoderma (bacterial skin infections), yeast infections or Otitis (ear infection). In these cases, the pruritus (itching) is present only when secondary infections are left untreated. Concurrent gastrointestinal signs (frequent bowel movements, vomiting, diarrhea, gas are reported in 20-30% of cases.
- Diagnosis- Intradermal or serologic (blood) allergy testing is not recommended because test results are unreliable. Response to hypoallergenic diet trial, symptoms improve within 10-12 weeks of initiation of a strict home-cooked or commercially prepared restricted diet (one protein and one carbohydrate). The hypoallergenic diet should not contain food ingredients previously administered in dog food, treats, or table scraps. Nor should flavored heartworm preventative, flavored mediations, nutritional supplements, or chewable treats (pigs ears, cows hooves, rawhides, dog biscuits, table food such as cheese or peanut butter to hide pills in) be used during trial.
- Treatment- Any secondary skin infections (bacterial, yeast),Ear infection should be treated Controlling secondary infection is an essential component of treating food allergic dogs. A flea-control program should be instituted to prevent flea bites from aggravating the itch. Food trial identifying offending substances to avoid. Prognosis is good. In dogs that are poorly controlled, owner noncompliance should be ruled out, along with development of hypersensitivity (allergy) to an ingredient in hypoallergenic diet, secondary infection, scabies, demodicosis, atopy, flea allergy, dermatitis, and contact hypersensitivity.