If the patient develops the following symptoms suddenly after medication: 1. Respiratory symptoms caused by laryngeal and bronchial edema and spasm: chest tightness, shortness of breath. Difficulty in breathing. If the patient has any of the following symptoms: 1) respiratory symptoms caused by laryngeal and bronchial edema and spasm: chest tightness, shortness of breath, difficulty in breathing. 2) circulatory symptoms: pallor, cold sweat, weak pulse, decreased blood pressure; 3) loss of consciousness, incontinence, fainting, coma, allergy/anaphylactic shock should be considered, once the allergic reaction to lidocaine occurs, the patient should be immediately made to lie down or the head and trunk should be slightly elevated to facilitate breathing, and the lower limbs should be elevated 15 to 20 degrees to facilitate venous return and to keep respiration open. Maintain a relatively normal body temperature. The patient should be resuscitated urgently, with immediate intramuscular injection of epinephrine and, if necessary, intramuscular intravenous dexamethasone, 2 to 20 mg at a time, and attention should be paid to in situ resuscitation. At the same time of the above resuscitation, apply antihistamines and intravenous adrenocorticosteroid drugs.