CPT code 90636 describes an adult intramuscular combined hepatitis A and hepatitis B vaccine product administered to provide immunization against both liver infections; the service is a vaccine administration typically performed in outpatient clinic or physician office settings and is billed as an immunization procedure for adult patients.

For related coverage guidance, see recent payer policy updates: B-Hemolytic Streptococcus Testing, Human Immunodeficiency Virus (HIV) — Coverage Criteria for Testing and Resistance Assays, Hepatitis Testing (A, B, C, D) Coverage Criteria.