• Code Z23 is for encounters for inoculations and vaccinations. • It means patient is being seen to receive a prophylactic inoculation against a disease. • Code Z23 may be used as a secondary code if the inoculation is given as a routine part of preventive health care, such as a well-baby visit.
Code Z23, which is used to identify encounters for inoculations and vaccinations, indicates that a patient is being seen to receive a prophylactic inoculation against a disease. If the immunization is given during a routine preventive health care examination, Code Z23 would be a secondary code.
Coding: Bill with 90471 only (If another vaccine is given at the same visit, code the administration fee for the second injection with 90472.) When billing for multiple vaccine administrations, you can either report administration add-on codes per line or report as multiple units on one line.
Z23 may be used as a primary diagnosis for immunizations in the OP and physician setting.