The Medicare Part D program provides prescription drug coverage. You can sign up for a stand-alone Medicare Part D Prescription Drug Plan to work alongside your Original Medicare coverage, or you can get all your Medicare coverage through a Medicare Advantage Prescription Drug plan.
If you enroll in a stand-alone Medicare Prescription Drug Plan (or a Medicare Advantage Prescription Drug plan), make sure you choose a plan that covers your medications. Every Medicare Prescription Drug Plan has a formulary that lists the drugs it covers, and many plans make their formularies available online. A plan’s formulary may change at any time. You will receive notice from your plan when necessary.
Most beneficiaries have to pay a premium for Medicare Part D, along with other costs such as copayments and coinsurance; these costs vary among plans. Although this insurance is optional, if you don’t enroll when you’re first eligible for Medicare, you could face a late enrollment penalty if you decide you want this coverage later on.