MedicaidCoverageMedium impact
Thiopurine S-Methyltransferase Enzyme Activity Testing - MEDICAID - INDIANA (New)
Humana·IN · Oncology, Gastroenterology, Rheumatology +1 more·Pharmacy
We identified it
Jul 23, 2026
Summary
Indiana Medicaid has established a new coverage policy for Thiopurine S-Methyltransferase (TPMT) enzyme activity testing. This test measures TPMT enzyme levels to identify patients at risk for severe toxicity before starting thiopurine drugs (azathioprine, mercaptopurine, thioguanine) and to guide appropriate dosing. Billing teams must verify coverage and prior authorization requirements for this test when ordering or processing claims.
Action Required
Immediately: Billing and clinical teams must review this new Indiana Medicaid policy for TPMT enzyme activity testing. (1) Verify the specific CPT code(s) covered for TPMT testing in your billing system and update documentation accordingly. (2) Determine if prior authorization is required before ordering—contact Indiana Medicaid or check the full policy at the source URL. (3) When patients on Indiana Medicaid require thiopurine therapy, ensure TPMT testing is ordered and documented per this policy to support medical necessity. (4) Train providers and front desk staff to flag thiopurine prescriptions for TPMT testing verification. (5) Update encounter templates or order entry systems to prompt for TPMT testing before thiopurine initiation. Failure to comply may result in claim denials or coverage disputes for subsequent thiopurine therapy claims.