Siemens Medical Solutions Diagnostics recently launched a new blood test for detecting allergies called 3gAllergy. Unlike skin tests, this technique can identify reactions to more than 400 allergens, including insect venom, foods like peanuts and milk and everyday pollen and mold. Another advantage is that aside from the short discomfort (ok, maybe a bit of pain) during withdrawal of the blood sample, there are no itchy welts to deal with if the allergy tests turn out positive. This technique is thus particularly good for children, even infants.

From the company website, addressing physicians:

3gAllergy is a new generation of allergy blood testing. It provides quantitative determination of allergen-specific IgE at very low levels with excellent precision, accuracy and lot-to-lot reproducibility. The assay delivers reliable results in about an hour to help you identify, monitor and manage patients with allergic diseases.

Here's an article from the Enquirer, comparing the 3gAllergy test to the conventional skin-prick test. If there's a hospital or facility which can run such a diagnostic test, perhaps your allergist may recommend it, too.