Prescription drugs are generally not covered by Original Medicare nor Medigap plans. Medicare Part D, also called Medicare Precription Drug plans, are available through private insurance companies contracted with Medicare to offer this coverage. Medicare Prescription Drug plans assign each drug a set copay/coinsurance which you can review before selecting a plan
Any beneficiary who is eligible for Original Medicare, Part A and/or Part B, and is a permanent resident of the Medicare Prescription Drug Plan service area, can sign-up for Medicare Prescription Drug Plan. Part D coverage is optional, but if you don’t enroll in a Medicare Prescription Drug plan as soon as you’re eligible, you might pay a late-enrollment penalty if you enroll later.
Beneficiaries can get Part D coverage with a stand-alone Medicare Prescription Drug Plan if they’re enrolled in Original Medicare, or, with a Medicare Advantage Prescription Drug Plan (MAPD). A stand-alone Medicare Prescription Drug plan works alongside Original Medicare. A MAPD plan is a Medicare Advantage plan that includes prescription drug benefits. Different insurers offer different types of plans, so your monthly plan premium and out-of-pocket expenses for prescription drugs will vary from plan to plan.
You can learn more about Prescription Drug plans here.