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What is Medicare Prescription Drug Coverage

Medicare's prescription drug coverage (also called Part D) is a program to help people on Medicare pay for medications. You can add Part D to Original Medicare, as well as to certain other Medicare plans. Another way that you can get prescription drug coverage is to enroll in a Medicare Advantage Plan that offers drug coverage.

Who Is Eligible?

Most people who are 65 years and older or are disabled can enroll in Medicare, including Medicare drug plans.

When Should I Enroll?

You can enroll in Medicare around your 65th birthday—3 months before your birthday month to 3 months after. If you have a disability, you can enroll during a 7-month window around your 25th month of disability. Also, Medicare has an open enrollment period from October 15 through December 7.

What Does It Cover?

Private health insurance companies administer the drug plans for Medicare. These companies provide a list of brand-name and generic drugs that they cover. The list can change over time. It is common for drug plans to exclude more expensive brand-name medications if a generic one is available. However, if there is a medication that you really need, your doctor may be able to appeal and get the drug covered.

What Does It Cost?

The costs depends on different things—the medications you use, the plan you choose, and whether you go to a pharmacy in your plan’s network. Here are some costs you can expect to pay:

  • Monthly premium—This is the monthly fee that drug plans charge.
  • Yearly deductible—This is the amount of money you must pay for your prescriptions before your plan begins to pay.
  • Co-payments—This is the amount you pay at the pharmacy for your covered prescriptions after the deductible has been reached.
  • Coverage gap—Most drug plans have a coverage gap. After you and your drug plan have spent a certain amount of money for your covered medications, you have to pay all costs out-of-pocket for your prescriptions up to a yearly limit.
  • Catastrophic coverage—After you have spent up to your plan’s out-of-pocket yearly limit for covered drugs, this allows you to only pay a small co-payment for the drug for the rest of the year.
  • Late enrollment penalty—This penalty is added to your Part D premium if you have a period of time when you have not been covered by Part D or another prescription drug plan.

Are There Ways to Lower the Costs?

Yes, there are steps that you can take to lower your costs, such as:

  • Switching to a generic medication or less expensive brand-name
  • Finding out if your state offers a pharmaceutical assistance program.
  • Applying for help through Medicare and Social Security

How Should I Make My Decision?

By answering a few questions, you should be able to choose a plan that works best for you:

  • What drugs are you taking now? Does the Medicare plan you are considering cover most of the costs for those drugs?
  • Does the pharmacy you use most often carry the drugs covered by the plan? Here, your pharmacist can help you to choose the right plan.
  • How much can you afford to spend on a drug plan?
  • Do you have all the information about other insurance coverage you may have?
  • Is the plan you are considering flexible enough to change if your health changes?

How Can I Get More Information?

Visit the US Medicare website to learn more about their health insurance plans and drug coverage. If you are eligible, you can even sign up online for Part D.



Social Security


Drug coverage (Part D). Medicare website. Available at: Accessed August 23, 2017.

Enrolling at the right time. AARP website. Available at: Updated July 29, 2015. Accessed August 23, 2017.

Extra help with Medicare prescription drug plan costs. Medicare website. Available at: Accessed August 23, 2017.

Get help paying costs. Medicare website. Available at: Accessed August 23, 2017.

Medicare Advantage plans. Available at: Accessed August 23, 2017.

Medicare and you: 2017. Medicare website. Available at: Accessed August 23, 2017.

Last reviewed August 2017 by EBSCO Medical Review Board Michael Woods, MD, FAAP  Last Updated: 10/31/2013