Medicare Part D, the prescription drug benefit, is the part of Medicare that covers most outpatient prescription drugs. If you are an eligible participant you pay a monthly premium to a private insurance carrier for your Part D plan. In return, you use the insurance carrier's network of pharmacies to purchase your prescription medications. The federal government subsidizes premiums and contributes to cost-sharing.
If you are a veteran who is enrolled in the VA health care system (or qualify based on one of the exceptions in the law) you are eligible to get your prescribed medications through a VA Outpatient Pharmacy. You do not need to enroll in Medicare Part D.
However, there can be situations where it is advantageous to sign up for Part D such as when a VA Pharmacy is too far away or when a specific prescription is not available through the VA. If you enroll in VA drug coverage and Part D coverage, bear in mind that the two do not work together. Part D will only pay at pharmacies in your plan’s network and the VA will only pay at VA pharmacies and clinics.
Under Medicare rules, if you enroll in a Part D plan after the Initial Enrollment Period ends you will be charged a penalty. You are exempt from the penalty if you have had “creditable drug coverage”. VA medication coverage is considered creditable drug coverage. You should receive a notice from the VA letting you know that your coverage is, in fact, creditable. You should keep this notice. If you decide later you want Medicare prescription drug coverage, you may be required to show proof that you had creditable coverage.