Key Takeaways

• Your Medicare Part D plan in 2025 may not cover every prescription you expect, even if it’s common or necessary. Coverage decisions depend on your plan’s formulary, tiers, and rules.

• Knowing how to verify drug coverage, request exceptions, and handle denied claims can help you avoid high out-of-pocket surprises at the pharmacy counter.

What a Formulary Really Tells You

Every Medicare Part D plan has a formulary—the list of drugs it covers. But this list isn’t one-size-fits-all. In 2025, formularies continue to vary widely across plans, and your coverage depends on:

• Whether your medication is included at all

• What tier it falls under (affecting your cost)

• Any restrictions, such as quantity limits, prior authorization, or step therapy

Drugs are divided into tiers, typically ranging from preferred generics to non-preferred brands and specialty drugs. Even if your drug is listed, being placed in a high-cost tier could mean significantly higher copayments or coinsurance.

What’s Not Covered: Common Drug Exclusions

Some drugs are excluded entirely from Medicare Part D coverage. Plans are not required to cover:

• Drugs for weight loss or weight gain

• Fertility medications

• Over-the-counter medications (even with a prescription)

• Cosmetic treatments, such as hair growth

• Drugs for erectile dysfunction (with few exceptions)

These exclusions apply regardless of your medical need. If your treatment falls under one of these categories, you’ll have to pay the full retail price unless you have other coverage or qualify for a patient assistance program.

When Your Drug Isn’t on the Formulary

If your medication isn’t listed on your plan’s formulary in 2025, you still have a few options:

• Ask your doctor if there’s a covered alternative. Sometimes a similar drug in a lower tier is just as effective.

• Request a formulary exception. This involves your doctor submitting documentation to the plan showing why you need the non-covered drug.

• File an appeal if denied. You have the right to appeal the decision if your exception request is denied.

Keep in mind that approval isn’t guaranteed, and the process can take time. It’s best to check your plan’s formulary every year during Medicare Open Enrollment (October 15 to December 7).

Prior Authorization, Step Therapy, and Quantity Limits

Even if your medication is covered, that doesn’t mean it’s automatically available at the pharmacy. In 2025, most Part D plans use these management tools:

• Prior authorization: You must get approval from the plan before filling certain prescriptions.

• Step therapy: You’re required to try lower-cost drugs first before the plan pays for a more expensive one.

• Quantity limits: There’s a cap on how much medication you can get at one time.

These rules aim to control costs and ensure appropriate use, but they can also delay treatment or result in denials if not followed correctly.

How Tier Placement Impacts What You Pay

Even if a drug is covered, its placement in a higher tier means you’ll pay more. Here’s how tiers typically break down:

• Tier 1: Preferred generic – lowest cost

• Tier 2: Generic – slightly higher cost

• Tier 3: Preferred brand-name – moderate cost

• Tier 4: Non-preferred drug – higher cost

• Tier 5: Specialty drug – highest cost

In 2025, plans can update their tier structures annually. That means a drug that was Tier 3 in 2024 could be moved to Tier 4 this year, increasing your cost without warning unless you carefully review your Annual Notice of Change letter.

How to Check What Your Plan Covers

To avoid pharmacy counter surprises, here’s how you can verify your drug coverage:

• Use your plan’s online formulary lookup tool

• Call your plan’s customer service

• Talk to your doctor about whether your prescribed medication is covered

It’s also smart to ask your pharmacist, especially if you’re starting a new prescription. They can often flag issues with coverage or suggest alternatives.

Switching Plans if Coverage Isn’t Right

If your Part D plan doesn’t meet your needs, you’re not stuck. Medicare Open Enrollment from October 15 to December 7 each year allows you to:

• Change to a different Part D plan

• Switch to a Medicare Advantage plan that includes drug coverage

Any changes you make during this window take effect January 1 of the following year. If you missed enrollment or experienced a qualifying life event, you might qualify for a Special Enrollment Period.

What Happens at the Pharmacy

You may assume your prescription is covered until you’re told otherwise at the pharmacy. Common situations that catch people off guard include:

• The drug isn’t on your plan’s formulary

• The pharmacist says prior authorization is required

• You’ve hit a quantity limit and can’t get more

• The medication is in a high tier and comes with steep coinsurance

Pharmacists can’t override plan rules, but they can help you understand the issue and contact your plan or prescriber.

Denials and Appeals: Know Your Rights

If your drug is denied at the pharmacy, you have appeal rights. The process includes:

1. Coverage Determination: Request your plan to cover the drug. Your doctor may need to submit medical justification.

2. Redetermination (First-Level Appeal): If denied, request a review by your plan.

3. Independent Review: If still denied, an independent entity reviews the case.

4. Administrative Law Judge Hearing: Further appeal if necessary.

You also have the right to request a fast (expedited) decision if your health is at risk.

The 2025 $2,000 Out-of-Pocket Cap—What It Doesn’t Cover

This year, a major improvement to Medicare Part D is the $2,000 annual cap on out-of-pocket drug costs. However, there are some important caveats:

• It applies only to drugs covered under your plan’s formulary

• Drugs not covered by your plan won’t count toward the cap

• Costs from over-the-counter medications or excluded drugs don’t apply

So, if you pay for a non-covered medication, that expense won’t get you closer to the $2,000 limit.

Coordination With Other Coverage

If you have additional prescription coverage through a retiree plan, Medicaid, or TRICARE, it may change how your Part D benefits work. Be sure to:

• Let your Part D plan know about any other coverage

• Understand how claims are coordinated

• Review Explanation of Benefits (EOB) statements to see what’s applied toward your costs

Sometimes other insurance will pay first, reducing what Part D covers or counts toward your out-of-pocket cap.

Keeping Up With Changes Year to Year

Formularies and costs change every year. That’s why reviewing your Annual Notice of Change is critical. It tells you:

• What’s changing in your plan for the new year

• Which drugs are being added or removed

• Tier shifts that may affect your cost

You should compare plans during Medicare Open Enrollment even if you’re happy with your current one. A better fit might be available.

Don’t Wait Until You’re at the Counter

Understanding what your Medicare Part D plan covers in 2025 is essential—not just when you’re sick, but all year long. Waiting until you’re at the pharmacy to find out your medication isn’t covered can lead to delays, frustration, or high out-of-pocket costs.

Check your formulary. Know the tiers. Look into your options for alternatives or exceptions. And if you’re unsure, get help.

Avoid Surprises—Understand Your Drug Coverage Now

Staying informed about what your Medicare Part D plan covers in 2025 will help you make smarter decisions before you fill a prescription. If you’re uncertain about coverage, costs, or the exceptions process, it’s worth reaching out for assistance.

Speak with a licensed agent listed on this website to explore your Medicare drug coverage questions. Don’t wait until the pharmacy tells you what your plan won’t pay for.