SELECTED ARTICLES FROM THE RECENT LITERATURE 2003

12/8/03

Evaluation of patients with reported adverse reactions to local anesthetics

Summary
Individuals with histories of adverse reactions to local anesthetics (LA) are commonly referred to allergists for evaluation even though previous evidence indicates that true allergy to LA is extremely uncommon. Berkun et al of the Bikur Cholim Hospital in Jerusalem, Israel reviewed their experience with 236 patients referred to them for evaluation because of a history of adverse systemic reactions following injection of LA. They found that prick and intradermal skin tests using LA were negative in all these individuals. A subsequent subcutaneous challenge with a LA unrelated chemically to the agent reported to have caused the adverse reaction (but containing the preservatives used in commercial LA agents) showed an objective adverse reaction (local erythema) in only one subject of the entire group. The authors felt that their skin test/subcutaneous challenge protocol could be abbreviated in face of the relative rarity of positive responses they have previously encountered.

Reference
Ann Allergy Asthma Immunol 2003;91:319-20

Editor's Comments
The findings described above are quite similar to that reported previously by other groups. Yet a number of patients are still seen with histories of "allergy" to LA. Some investigators feel that such subjective reactions (generally without accompanying objective manifestations) are most likely psychologic - perhaps a reflection of the stress felt by a person undergoing the medical procedure involving injection of LA. However, I think that there are other, more physiologic, explanations. It is well known that injection of large doses of LA over a short time period can sometimes induce quite prominent neurologic (e.g., tingling sensation) and cardiac (e.g., palpitations) effects. Some individuals may be very sensitive to such systemic effects of LA with (to them) frightening manifestations.

<-- BACK