Ear Itching and Infections
Ear infections in pets (otitis externa) may be more common than skin infections because the ear is often the first part of an allergic pet's body to develop itching. Half of dogs with allergies have ear infections as their only obvious problem. Over time, these infections can progress to chronic ear inflammation and deafness.
Some allergic pets itch more than ever when they come home from the groomer. This occurs if the groomer uses heavily scented soaps and conditioners. Some groomers clip the hair so short, especially along the bottom, that the clippers further irritate already itchy skin. If your pet has allergies, he or she may come home from the groomer and rub him or herself on the floor, carpet, and sofa.
Pet Skin Infections Caused by Allergies
If your cat or dog is scratching frequently, bacteria can enter breaks in the skin and begin multiplying. Some of these bacteria, such as Staphylococcus, Streptococcus and Pseudomonas, cause serious infections so that your pet needs antibiotics to recover. Antibiotics clear the skin infection but do not remove the underlying problem, which is allergies. Without addressing the tendency to be allergic, cycles of reoccurring skin and ear infections are likely.
Many pets with allergies slide on their bottoms (scooting) because the rectal area itches. Scooting looks funny but aggravates the two anal sacs located on either side of the rectum and anal sac abscess occurs.
Pet Allergies and Digestive Problems
Pets with food allergies may burp and vomit, pass gas, have diarrhea, and lose weight. Some do not have diarrhea, but have frequent stools. Food allergies are the third most common cause of skin disease after flea allergies and atopy.
Proteins cause most food allergies. It's unusual for pets to be allergic to carbohydrates or fats. Considering all dog food allergies, two-thirds are caused by beef, dairy, and wheat. Dogs are also frequently allergic to soy, chicken, eggs, and corn. For cats, 90% of food allergies are caused by beef, dairy, and fish. Cats are also commonly allergic to lamb, wheat, chicken, and corn.
For dogs and cats, the most common sign of food allergy is itching and scratching. Other signs of food allergies are head and neck itching, miliary dermatitis, eosinophilic granulomas, swollen lymph nodes, hives, and conjunctivitis.