Medicare Coverage of Mounjaro: What You Need to Know

Medicare Part D covers Mounjaro (tirzepatide) for type 2 diabetes, but coverage depends on your specific plan and whether your doctor's prescription meets your plan's requirements. Most plans place Mounjaro on their formulary — the list of covered drugs — but many require you to try other diabetes medications first or to get prior authorization before the plan will pay. The amount you pay out of pocket varies by plan and by which coverage stage you are in during the year.

Original Medicare (Part A and Part B) does not cover Mounjaro on its own. You must have Part D prescription drug coverage, either through a standalone Part D plan or through a Medicare Advantage plan that includes drug coverage. If you do not have Part D coverage, you can enroll during the annual enrollment period (October 15 to December 7) or during a special enrollment period if you lose coverage.

Key Takeaways

  • Mounjaro is covered by most Medicare Part D plans, but your plan may require prior authorization or that you try other medications first.
  • You pay a copay or coinsurance amount that depends on your plan's tier for Mounjaro and which coverage stage you are in during the year.
  • Your out-of-pocket costs change as you move through the deductible, initial coverage, and catastrophic coverage stages.
  • Contacting your Part D plan directly is the fastest way to find out whether Mounjaro is covered under your specific plan and what your costs will be.
  • If your plan denies coverage, you can request an appeal or ask your doctor to submit a prior authorization request with clinical justification.

How to Check Your Plan's Coverage of Mounjaro

The first step is to find out whether Mounjaro is on your plan's formulary. You can do this by calling the customer service number on the back of your Part D card, visiting your plan's website, or using the Medicare Plan Finder tool at Medicare.gov. Have your plan name and member ID ready when you call.

When you contact your plan, ask three specific questions: Is Mounjaro on the formulary? Does the plan require prior authorization? Does the plan require step therapy — meaning you must try and fail on other diabetes drugs first before Mounjaro is covered? The answers to these questions will tell you whether you can start Mounjaro right away or whether your doctor will need to submit paperwork first.

What You Pay: Copays, Coinsurance, and Coverage Stages

Your out-of-pocket cost for Mounjaro depends on two things: the tier your plan assigns to the drug and which coverage stage you are in during the calendar year. Most plans place Mounjaro on Tier 3 or Tier 4, which means higher copays or coinsurance than generic drugs. A Tier 3 copay might be $50 to $75 per month, while Tier 4 might be $75 to $150 or more, but these amounts vary widely by plan.

As you fill prescriptions throughout the year, you move through coverage stages. First you pay toward your deductible (usually $505 in 2024, but this varies by plan). Once you meet the deductible, you enter initial coverage and pay your copay or coinsurance. When your total out-of-pocket spending reaches a certain amount (usually around $7,050 in 2024), you enter catastrophic coverage and pay a small copay while Medicare and your plan cover the rest. The exact amounts change each year.

Because Mounjaro is a brand-name drug and often placed on a higher tier, you may reach catastrophic coverage sooner than you would with a generic medication. Ask your plan for an estimate of your total out-of-pocket cost for the year if you use Mounjaro monthly.

Prior Authorization and Step Therapy Requirements

Many Medicare Part D plans require prior authorization before they will cover Mounjaro. This means your doctor must submit a request to the plan explaining why you need the drug. The plan then reviews the request and either approves it, denies it, or approves it with conditions (such as requiring you to try another drug first).

Step therapy, also called fail-first, requires you to try other diabetes medications before the plan will cover Mounjaro. For example, your plan might require you to try metformin or a GLP-1 drug like semaglutide first. If those drugs do not work for you or cause side effects, your doctor can then request Mounjaro. This process can delay your access to the drug by weeks or months.

If your plan denies coverage or requires step therapy, your doctor can appeal the decision or submit additional clinical information to support the request. You also have the right to request an expedited review if your doctor believes the delay could harm your health.

Medicare Advantage Plans and Mounjaro Coverage

If you have a Medicare Advantage plan (Part C) that includes prescription drug coverage, Mounjaro coverage works the same way as with standalone Part D plans. The plan has its own formulary, its own prior authorization rules, and its own copay or coinsurance amounts. Some Medicare Advantage plans may cover Mounjaro more generously than others, so it is worth checking your specific plan's coverage.

If you are thinking about switching to a different Medicare Advantage plan during the annual enrollment period, you can compare drug coverage as part of your decision. Use the Medicare Plan Finder to see which plans in your area cover Mounjaro and at what cost.

What to Do If Your Plan Does Not Cover Mounjaro

If your plan denies coverage or requires step therapy you do not want to follow, you have several options. First, ask your doctor to submit a prior authorization request with clinical justification — for example, if you have tried other drugs and they did not work, or if you have a condition that makes Mounjaro the best choice. Many denials are overturned on appeal.

Second, you can switch to a different Part D plan during the annual enrollment period (October 15 to December 7) if another plan in your area covers Mounjaro with lower out-of-pocket costs. Use the Medicare Plan Finder to compare plans side by side.

Third, you can ask your doctor about other GLP-1 or SGLT2 inhibitor drugs that your plan may cover more readily. Semaglutide (Ozempic), dulaglutide (Trulicity), and other diabetes drugs may be covered with lower copays or without step therapy requirements.

Finally, if you cannot afford Mounjaro even with insurance, Eli Lilly (the manufacturer) offers a patient information program that may reduce your copay to as low as $25 per month if you meet income requirements. Ask your doctor or pharmacist how to enroll.

Frequently Asked Questions

Does Original Medicare cover Mounjaro without Part D?

No. Original Medicare (Part A and Part B) does not cover outpatient prescription drugs. You must have Part D coverage, either through a standalone plan or a Medicare Advantage plan with drug benefits, to have Mounjaro covered by Medicare.

What if I cannot afford the copay for Mounjaro?

Eli Lilly offers a copay information program that can reduce your out-of-pocket cost to $25 per month if your household income is below a certain threshold. Ask your doctor or pharmacist for the enrollment form, or visit the Mounjaro website. Some community health centers and pharmaceutical information organizations also offer help.

Can I switch Part D plans to get better coverage of Mounjaro?

Yes. During the annual enrollment period (October 15 to December 7), you can switch to a different Part D plan or Medicare Advantage plan. Use the Medicare Plan Finder to compare which plans cover Mounjaro and at what cost in your area. You can also switch if you lose coverage or have a may have access to life event.

What happens if my doctor prescribes Mounjaro but my plan requires step therapy?

Your doctor can request an expedited review or appeal if they believe step therapy would delay necessary treatment. They can also submit clinical information explaining why you need Mounjaro specifically. Many plans approve these requests, especially if you have already tried other medications without success.

Is the cost of Mounjaro the same on all Medicare Part D plans?

No. Each plan sets its own copay or coinsurance amount for Mounjaro, and the tier placement varies by plan. Some plans may cover Mounjaro on Tier 3 with a $50 copay, while others place it on Tier 4 with a $100 or higher copay. Always check your specific plan's formulary to know your exact cost.