If tetanus vaccination is required due to an injury, one injection is sufficient. There are two types of tetanus shots. One is called tetanus antitoxin, which is extracted from horse serum. For this, a skin test is needed to check for allergies. If allergic, tetanus antitoxin cannot be used; if not, it can be used. The other type is refined tetanus antitoxin, also known as tetanus immune globulin, extracted from human serum. This type does not require a skin test and can be used directly, but it is more expensive than tetanus antitoxin. If tetanus treatment is needed for each injury, one injection is sufficient.