Skin testing protocol for patients with histories of possible IgE-mediated reactions to local anesthetics

Prick (epicutaneous) testing is performed initially, with appropriate positive (histamine) and negative (diluent) controls. Results are assessed at 20 minutes. A positive result consists of a wheal 3 mm greater than the negative control. If prick tests are negative, then intradermal testing is performed by injecting 0.02 mL of a 1:100 dilution of the local anesthetic in question.