TAT skin test is tetanus antitoxin skin test, its positive skin test results are mainly judged by the following criteria: the appearance of significantly enlarged dermatome at the site of the skin test, the dermatome of the phenomenon of obvious redness and swelling or dermatome of the phenomenon of infiltration of the surrounding tissues, the patient feels obvious itching symptoms, dermatome around the phenomenon of the tail-foot, all of these are tetanus antitoxin skin test test test is positive manifestations. Tetanus antitoxin can effectively prevent the infection of tetanus bacillus and can also be used for the treatment of tetanus bacillus after infection. If the tetanus antitoxin skin test is positive, desensitization therapy is possible. However, some patients may experience hives, frequent sneezing, itching of the nasal mucosa or throat during the skin test, which would be a strong positive reaction, in which case the desensitization test cannot be performed and can only be avoided.