What is Medicare Part D? | Most Asked Medicare Questions

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What is Medicare Part D?

Part D, also called PDP,  is prescription drug coverage for beneficiaries. This coverage comes in the form of prescription drug plans from Medicare-approved private insurance providers.

Who can get Part D coverage?

Anyone who is eligible for Part A or Part B coverage is also eligible for Part D. To be eligible for coverage, you must be a US citizen and meet one or more of the following criteria:

  • Are 65 or older
  • Have a disability
  • Have End-Stage Renal Disease (ESRD)

What does it cover?

Part D covers prescription drugs and any vaccines that are considered medically necessary to prevent illness. However, there are several rules and limitations to the coverage that patients should be aware of—and this is where things can get a bit confusing. The plans come from private insurers, which means that each one has a different formulary, or list of drugs that are approved, as well as a different set of rules for coverage. Here are two of the common coverage limitations you might run into:

  • Prior authorization. Prior authorization is when an insurance company requires either you or your doctor to contact it and prove that a drug is medically necessary before it will cover the drug. This is not exclusive to Part D plans, but it is common among them.
  • Step therapy. Step therapy is when the insurance company requires you to try at least one similar, lower-cost alternative before a prescribed drug will be covered.

What does it not cover?

Due to the different approved drug list each provider offers, not every drug will be covered under every plan. Make sure to check the formularies of any plans you’re considering to be sure they cover the drugs you take.

How do I enroll in a Part D plan?

There are several ways you can enroll:

    • Visit the website of the insurer that offers the plan
    • Use the the government website’s Plan Finder
    • Call the insurance company that offers the plan you want
    • Call 1-800-MEDICARE (1-800-633-4227)

<li”>Print off and fill out a paper enrollment form

When can I enroll?

There are two different times when you can sign up:

  • Initial Enrollment Period. This is a seven-month enrollment period when you become eligible for the first time. The Initial Enrollment Period—sometimes shortened to IEP—runs the three months before you turn 65, the month you turn 65, and the three months after you turn 65. If you are eligible due to a disability, your IEP includes the three months before your 25th month of disability benefits, your 25th month of disability benefits, and three months after your 25th month of disability benefits.
  • Open Enrollment Period. This is a period from October 15 to December 7 each year, during which you can join, make changes to, or drop a PDP.

What are the alternatives this type of plan?

Part C, also known as an Advantage Plan, is an alternative to Part D. These are plans from private insurers that bundle your Part A (hospital) and Part B (medical) coverage together into one plan. They often include prescription drug coverage as well. The benefit of an Advantage Plan is the simplicity of having everything covered under a single plan. A potential downside is that you are subject to the private insurer’s rules, which can include limited provider networks.

If you have questions about joining or switching plans, visit our FAQs to learn more.

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