Most of the symptoms of generalized itching after surgery are related to allergies. During and after surgery, more disinfectants, antibiotics or drugs to support blood circulation need to be applied, and these drugs may cause certain allergic reactions in patients. For example, when disinfecting, some people may be allergic to alcohol, and the disinfected area will show redness, swelling, itching and other sensations. When the skin shows only itching, etc., and no other obvious symptoms, such as laryngeal edema, etc., usually no special treatment is needed, and the allergic reaction will disappear when the drug metabolism disappears or the drug is discontinued. If the allergic reaction is severe and symptoms such as chest tightness and difficulty in breathing occur, the doctor should be informed in time to find out the condition and provide early treatment.