One of the most common reasons for which owners seek veterinary advice is due to skin problems. Cats and dogs develop skin diseases that range from fleas and lice, to allergies and sometimes even cancer.
Itchy skin is by far the most common presenting complaint. This can be due to several things. The most common would be allergies, divided into allergies to 1) inhaled allergens 2) food 3) fleas or rarely 4) contact allergies. Itchy skin in very young dogs and cats are commonly caused by ectoparasites (parasites on or in the skin - like fleas and scabies).
Dog and cats rarely manifest the same allergy symptoms as we do. They don't typically get watery, itchy eyes, and only sometimes sneeze. Their allergies usually manifest in the form of itchy skin - all over the body. A dog with chronic ear infections should certainly prompt the veterinarian to consider an underlying allergy of some sort.
Not only do dogs and cats get fleas, but they may become allergic to the bite of the flea (allergy to the fleas' saliva). Diagnosis in this case is more straightforward with treatment aimed at killing the fleas, ridding the environment of fleas, and providing itch relief to the pet in the form of antihistamines or steroids.
Dogs, and sometimes cats, chew their paws and forearm areas incessantly when they have allergies. If your dog's paws are rust-stained from constant licking and chewing, don't jump to the common belief that "it's just nerves." It's almost never nerves. It's allergies.
Cats often develop patchy hair loss from pulling out their own hair, and chronic licking. This occurs commonly on the belly, the neck, and hair loss on the face (ears and around the eyes).
The history, and ruling out of obvious diseases, will often prompt the vet to consider allergies as the underlying problem. A skin biopsy can help to make a diagnosis of allergies, but will NOT tell the vet what the pet is allergic to. Blood tests which measure the level of antibodies against a myriad number of allergens can help us with finding the source of the allergies (but should not be used to look for food allergies). These blood tests are variable in their accuracy. Skin testing tends to be preferable in the diagnosis of inhalant allergies (atopy).
Regardless of the type of allergy, it is incumbent on pet owners to recognize the symptoms so that at least relief can be provided to the itchy pet. A relatively new drug, called Atopica (cyclosporine), has been approved for the treatment of atopy in dogs.
Working a pet up with skin problems can be frustrating for everyone involved: the pet, the owners, and the vet. Be patient as response to a certain treatment will often, retroactively, help make a diagnosis!
See your vet if your pet is itchy - he or she will thank you!
A severe case of atopic dermatitis, taken from www.dermvet.com.
Intradermal testing: helps determine what the pet is allergic to (inhalant allergies - not food!).
A cat with inhalant (or food) allergies. Thanks dermvet.com.