Billing and Coding: Pharmacogenomic Testing

Medicare excludes duplicative germline pharmacogenomic testing (single‑gene or panel) that repeats previously tested genetic content in the same beneficiary and specifically deems CPT 81355 (VKORC1) and 81227 (CYP2C9) not reasonable/necessary for warfarin testing; testing may be allowed only for non‑duplicative panel components with established clinical utility. Providers must verify prior germline testing before billing, follow LCD L39995 and NCD guidance, and bill any non‑covered services with the appropriate modifier.