MedicaidAdministrativeHigh impact
Diagnosis Code Requirement on Certain Pharmacy Claims
Missouri Medicaid (MO HealthNet)·MO · Oncology, Hematology, Rheumatology +5 more·Pharmacy
Effective date
Jan 25, 2024
We identified it
Jun 20, 2026
Summary
Missouri Medicaid (MO HealthNet) now requires specific ICD-10 diagnosis codes on pharmacy claims for select high-cost drug classes including checkpoint inhibitors, complement inhibitors, PARP inhibitors, and targeted immune modulators. Pharmacies must enter diagnosis codes in NCPDP field 492-DO and verify codes are billable before submission.
Action Required
Immediately: Contact pharmacy software vendors to ensure system supports NCPDP field 492-DO for diagnosis code submission. Coordinate with pharmacies to ensure they obtain specific ICD-10 diagnosis codes from prescribers before filling claims for checkpoint inhibitors, complement inhibitors, PARP inhibitors, immunoglobulins, and targeted immune modulators. Verify all diagnosis codes are billable (not category codes like F20) before submission. Claims without required diagnosis codes may be denied.