Medicare generally covers your hospital stays, doctor visits, and medical treatments. But what about prescription drugs?

While Part A covers medications during hospital stays and Part B covers some drugs your doctor gives you in their office, Original Medicare doesn't cover most prescriptions you’d pick up at the pharmacy.

That's where Medicare Part D comes in. Part D is optional prescription drug coverage you can purchase to help reduce the cost of your medications.

In this guide, we’ll cover how prescription coverage works with Medicare, including what drugs are covered by Part A and B and how Medicare Part D works.

What drugs do Medicare Part A and B cover?

Both Medicare and Part A and Part B generally only cover medications you receive during a visit. Part A covers drugs you receive during a hospital or skilled nursing facility stay. Medicare Part B covers medications your doctor gives you. Part B may also cover several specific types of outpatient medications, including:

  • Vaccinations to prevent illness

  • Cancer drugs you take by mouth

  • Medications for dialysis patients

  • Injectable drugs given by your healthcare provider

  • Drugs used with medical equipment, like nebulizers

  • Nutrition given through IV or feeding tubes

  • Blood clotting medications

  • Drugs that help prevent organ transplant rejection

Some medications might be covered under either Part B or Part D, depending on how and where you receive them.

What do Medicare Part D plans cover?

Medicare Part D coverage can be obtained through a Medicare Part D plan or a Medicare Advantage plan that includes Part D (MAPD plan). Part D provides coverage for prescription medications, including insulin and blood pressure medication.

Part D should cover most prescriptions you need for medical purposes. Which drugs are covered by a plan depend on the plan’s list of drugs (known as a formulary). Each insurance plan will cover different prescriptions at different levels, so it’s important to look at how a Part D plan covers your medications, specifically. Make sure to look at a plan’s formulary, monthly premium, annual deductible, and coinsurance amounts.

Which medications aren't covered by Medicare Part D?

  • Over-the-counter (OTC) medications like aspirin, cough syrup, and cold remedies

  • Cosmetic medications to enhance appearance, such as hair loss treatments or anti-aging creams

  • Medications for weight loss or gain unless they are used to treat an underlying medical condition

  • Supplements and vitamins

  • Drugs used for recreational purposes that contain illegal substances

Who is eligible for Medicare prescription drug plans?

If you’re enrolled in both Part A and Part B, either through Original Medicare or Medicare Advantage, you’re eligible for Medicare Part D. 

If you qualify for both Medicare and Medicaid, you may be eligible for Extra Help for prescription drug costs. Those on Medicaid are often enrolled in a Part D drug plan and can receive financial aid to pay for medications. 

Learn more about how Medicare and Medicaid work together in our guide to Medicare vs. Medicaid.

Is Medicare Part D required?

Purchasing Medicare Part D coverage is voluntary. If you don’t sign up for Part D during your Initial Enrollment Period, however, you may have to pay the Part D enrollment penalty when you enroll in a plan later.

What does Medicare Part D cost?

In 2025, the average cost of a standalone Part D plan is $45 per month. Keep in mind that premiums can vary significantly depending on the plan and region. Typically premiums for Part D coverage are cheaper when coverage is included in a Medicare Advantage plan. Many Medicare Advantage plans even have $0 premiums. 

Your plan premium is what you pay to maintain insurance coverage, but you should also be aware of your out-of-pocket costs, including deductibles and coinsurance. Each Part D or Medicare Advantage plan will have its own out-of-pocket cost structures, and some “cheaper” plans could end up costing you more money because they don’t cover your prescriptions as well. To compare your out-of-pocket costs, look at a plan’s list of covered drugs (formulary) to determine what tier your drugs are on. From here, figure out what your copay or coinsurance will be each month. 

How do drug tiers and formularies affect Medicare prescription drug coverage?

Every company has a list of drugs they cover, known as their formulary, which puts specific medications into drug tiers.

TierType of MedicationYour Cost
Tier 1Most Generic MedicationsLowest Copay
Tier 2Common/Preferred Brand-Name Drugs and High-Cost Generic DrugsMedium Copay
Tier 3Non-preferred Brand Name DrugsHigh Copay
Tier 4Specialty and High-Cost DrugsPercentage of Drug Cost

The specific drugs in a formulary vary among companies, and so does pricing. A prescription may be considered a Tier 2 drug on one plan but a Tier 3 on another. When reviewing Part D prescription drug plans, checking your list of drugs against the plan's formulary will help you find the plan that will save you the most. Purchasing your prescriptions through mail order or at a plan’s preferred pharmacy can also help you save money.

What can you do if your prescription drug costs are too high?

When your healthcare provider writes a prescription, they may specify a brand-name drug and indicate that a lower-cost option would also work. If you need a lot of prescriptions or some of your prescriptions are costly, you may consider applying for Extra Help. You can also seek out coupons for common prescriptions and use websites like GoodRX and Cost Plus Drugs to find lower-cost prescriptions. 

Want to learn more about Medicare Part D and how Medicare covers prescriptions? Speak with one of our independent Medicare Advisors, who are eager to help you understand your coverage and how to get the most out of Medicare. Get in touch by calling us at (855) 900-2427 or picking a time to chat.

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