D2.235 - Is an allergy skin test with local anaesthetics necessary? Real life data with 124 patients

Local anesthetics (LAs) are widely used agents. However, although rare, allergic reactions may develop against these drugs. Allergic reactions can range from mild skin reactions to anaphylaxis. In this study, we investigated the subsequent drug exposure and reaction rates of our patients who were tested with LA.

The medical records of 124 patients who presented with suspected LA allergies at the Division of Allergy and Immunology, Ege University Medical Faculty, between February 2020 and August 2024 were retrospectively analysed. The patients included in the study were telephoned and questioned whether they used LA after the test and whether any reaction developed.

Of the 124 patients, 82% (n=102) were female. Most patients were referred from dentistry (55.7%, n=64) and anesthesiology (20.9%, n=24) departments. 51 patients were referred only for LA-related reactions, 23 patients were referred for reactions to other drugs, 50 patients were referred for reactions to LA and other drugs. Chronic urticaria was present in 13.3% (n=16) and asthma in 17.5% (n=21) of the patients. 44 patients did not know which LA they had a reaction with, while 40 patients stated that they had a reaction with lidocaine (Table 1). In 20 patients, general or spinal anaesthesia was performed simultaneously. Prick-intradermal (P-ID) and provocation tests were performed in all patients (n=35 suspected LA, n=26 alternative LA, n=63 random). P-ID test positivity was found in only 1 patient and provocation test with alternative agent was performed in this patient and the result was negative (Table 2). Of the 92 patients contacted by telephone, 53 patients were administered LA according to the test results and no allergic reaction developed, while the other 39 patients were not administered LA.

In this study, none of the patients who used LAs after testing experienced an allergic reaction. The fact that skin test positivity was found in only one patient may suggest direct provocation without testing in the other patient group by excluding serious reactions with a well-obtained anamnesis.