Question: For tetanus shots, weve been charging 90471 and 90703. What are the current rules on tetanus injection codes? South Dakota Subscriber Answer: Medicare covers a tetanus injection (90703,Tetanus toxoid adsorbed, for intramuscular use; 90714,Tetanus and diphtheria toxoids [Td] adsorbed, preservative free, when administered to individuals 7 years or older, for intramuscular use; 90718, Tetanus and diphtheria toxoids [Td] adsorbed when administered to individuals 7 years or older, for intramuscular use) when given for an acute injury to a person who is incompletely immunized. When a tetanus booster is given to a patient without an injury, the injection does not meet the coverage criteria for Medicare, although it may be appropriate preventive treatment. When a vaccination is excluded from coverage, related charges are also not covered.