Optum Rx (formerly Catamaran Rx) is the pharmacy benefit manager for MPSERS retirees. Visit the Optum Rx website for MPSERS retirees. Health Insurance Resources Health Insurance Resources Insurance Rates › MPSERS Insurance Information › Insurance Enrollment Change Request Form › Insurance Options Summary › Dependant Coverage › Insurance Subsidy Eligibility › Medicare and MPSERS: What to do when you turn 65 ›