Allergy Test: The RAST Test

Allergy Test: The Test: "How is it used?
The allergen-specific IgE antigen test is done to screen for an allergy (a type I hypersensitivity) to a specific substance or substances in response to acute or chronic allergy-like symptoms in the patient.

The allergen-specific IgE antibody test may be done (instead of other medically supervised allergy testing) when the patient has significant dermatitis or eczema, is taking necessary histamines or anti-depressants that would make other testing more difficult, or if a dangerous allergic reaction could be expected to follow another test.

The allergen-specific IgE antibody test may also be done to monitor immunotherapy or to see if a child has outgrown an allergy, although it can only be used in a general way; the level of IgE present does not correlate to the severity of an allergic reaction, and someone who has outgrown an allergy may have a positive IgE for many years afterward."
--this test may or may not prove what ails your bulldog, I'd try dietary changes before expensive testing.
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