Allergic reaction to epinephrine preparation in 2% lidocaine: two case reports.

We report 2 cases of hypersensitivity to an epinephrine preparation in local anesthetics which were found by skin tests for local anesthetics. Both patients had uncomfortable episodes to local anesthetics at dental treatment. In both cases, the skin tests showed positive reactions to 2% lidocaine with 1:80,000 epinephrine. Furthermore drug lymphocyte stimulation test revealed positive reaction to epinephrine hydrochloride, epinephrine bitartrate in case 1, whereas in case 2, the drug lymphocyte stimulation test showed positive response to epinephrine bitartrate. Attention should be paid to exogenous epinephrine preparations that have the potential to induce hypersensitivity during dental treatment.