Bradfordville Animal Hospital
Allergy Information

Overview

     Allergies are by far one of the most common, everyday problems facing both pet owners and veterinary hospitals. Although many questions about allergies would seem to be answered by common sense, a large number of clients are very surprised to learn that their pet's problems are due to allergies and the underlying reasons for this. Therefore, it is very important that proper information be provided to the pet owner to enhance understanding or the problem and encourage treatment compliance which will increase the likelihood of a successful outcome.

    In general, the underlying mechanism for all types of allergies is the same. After repeated exposure to a particular substance (the allergen), the body develops antibodies to that substance which can trigger the allergic response. The amount of allergen and the length of exposure needed for a reaction vary with the animal- hence, some animals may react quickly to a small amount of material while others may need a longer exposure time or a larger quantity of allergen. Other animals may not react at all.

    Another important point to know is that allergies tend to be cumulative. Animals have an allergy "threshold" and as long as the amount of exposure remains below that threshold, signs are usually minimal. Once the threshold is exceeded, clinical signs will become apparent. For example, Spot is a  dog who is allergic to mold spores, ragweed and house dust. During the winter, Spot's system is only exposed to house dust and though irritating, Spot's system can keep the allergic response under control. In the spring (when pollen season starts), Spot becomes very itchy, chews his feet and loses his hair. His allergy threshold has been surpassed and clinical signs are easily apparent.

Atopy

    The allergic condition relating to inhalant allergies is known as atopy. Anything in the environment that an animal can inhale into its respiratory tract can cause atopy, i.e. molds, pollens, grass and tree spores, etc.

Dogs

Average age of onset: 1-3 years, but may bee seen as young as 6-7 months.
Clinical signs: scratching, biting, hair loss, licking feet (especially between toes and pads). May also cause sneezing, reverse sneezing and snorting, chronic ear infections, sinusitis, watery eyes, conjunctivitis, greasy fur, flaky skin, bad odor. Secondary skin infections are also common; however, this may be seen with any of the allergy problems described.
Skin pattern: may be found anywhere on the body, especially feet, ears, eyes, axillae and groin.

Cats

Average age of onset: 1-3 years
Clinical signs: scabs associated with "miliary dermatitis", possibly scratching (this is not a consistent feature), excessive grooming, broken hairs, hair loss, excessive grooming, broken hairs, hair loss, asthma. May also be associated with eosinophlic granuloma complex, characterized by lip ulcers and skin plaques.
Skin pattern: Miliary dermatitis is usually seen on the head, neck, back and tail. Broken hairs may be found on the tail backs of rear legs, and belly (may be bald!).