The allergist may order some blood tests:
- CBC.
 - Levels of antibodies (mainly IgE antibody, the typical antibody of allergy).
 - IgE antibodies against specific allergens (see RAST/ELISA test).
 - Complement levels (C3 / C4).
 - Tests to rule out autoimmune diseases such as ANA.
 
The vast majority of patients do not need blood tests.

						
						

