Medicare AdvantageAdministrativeMedium impact
Illinois Cares Rx and Dual Eligible Enrollment Changes
Illinois Medicaid - HFS·IL · Pharmacy·Provider Notice
Effective date
Apr 5, 2006
We identified it
Jun 21, 2026
Summary
Illinois Cares Rx members and dual eligible Medicare/Medicaid beneficiaries may have switched Medicare Part D prescription drug plans or been newly enrolled, requiring updated eligibility verification. Claims may fail if billed to previous plans, so billing teams must verify current plan enrollment before processing prescription-related claims.
Action Required
Immediately when prescription claims fail: Perform E1 eligibility transaction to determine current Medicare Part D plan enrollment. If no enrollment found for dual eligibles, call Medicare at 1-800-medicare. For Illinois Cares Rx members, contact PacifiCare (1-800-797-9794) or United AARP (1-888-492-2952) first, then provider hotline (1-800-842-1461) if needed. Update patient records with current plan information.