Risk-stratified Testing for Safe Removal of Penicillin Allergy Labels

Patients will receive a 1-step or 2-step challenge with the suspected penicillin and will be monitored for any allergic reaction within the first four hours. Patients will be instructed to contact the hospital after the drug provocation test to inquire delayed allergic reactions.

The patient will receive skin prick test and patch test (if a delayed allergy is suspected). Allergen-specific IgE will be measured. If all negative, drug provocation tets will be performed identical to the experimental group.