Prescription DRUGS Your prescription drug plan is through CVS Caremark. CVS Caremark is your pharmacy benefit manager. The Caremark network includes most retail chain pharmacies such as Walgreens, CVS, Walmart, Meijer, Kroger, and Costco. Mail order prescriptions can be ordered directly through Caremark. A preventive drug list can be found using the Caremark Portal link below. Caremark Portal