It is very normal to get hot on the plaster, and the mechanism of this situation is mainly as follows: 1, it may be caused by the stimulation of drugs inside the plaster, some plasters contain Chuan Wu, Cao Wu, Radix et Rhizoma, White Mustard Seed, Nan Xing and other drugs. This kind of drug will have a benign stimulation after contacting the skin surface, and then make the patient feel feverish; 2. It may be caused by the heat of the plaster itself, such as some black plasters before use, to use fire to bake it, and then put it on, then the patient will feel feverish. Some of the plasters have self-heating materials, and after being applied, they will have a continuous hot compress effect on the patient, and the patient will also feel feverish; 3, may be caused by the acceleration of local blood circulation, some plasters contain a series of ingredients to activate blood circulation and eliminate blood stasis, so after use, it will accelerate the patient’s local blood circulation, and the patient will also feel the local fever.