Medicare's Coverage of Mounjaro

Medicare Part D (prescription drug coverage) covers Mounjaro, but only if your plan includes it on its formulary — the list of drugs the plan will pay for. Not every Part D plan covers Mounjaro, and the ones that do may require you to meet a deductible first, pay a copay or coinsurance, or get prior authorization from your doctor before the pharmacy fills your prescription.

Medicare Part B does not cover Mounjaro. Part B covers injectable drugs that are administered in a doctor's office or hospital, but Mounjaro is a self-injected drug you use at home, so it falls under Part D instead. If you do not have Part D coverage, you will pay the full retail price out of pocket unless you may have access to for a manufacturer discount program.

Your actual out-of-pocket cost depends on which Part D plan you chose and where you are in the plan year. Early in the year, you may pay only a copay. Once you reach the coverage gap (sometimes called the "donut hole"), your costs jump significantly until you reach catastrophic coverage later in the year.

Key Takeaways

  • Mounjaro is covered by Medicare Part D, but only through plans that include it on their formulary, and coverage varies by plan.
  • Your Part D plan may require prior authorization from your doctor before the pharmacy will fill the prescription.
  • You will pay differently depending on which stage of the plan year you are in — copay early on, higher costs in the coverage gap, and lower costs once you reach catastrophic coverage.
  • If you do not have Part D coverage, the manufacturer Eli Lilly offers a savings program that can reduce your cost to as low as $25 per month.

How to learn about Your Plan Covers Mounjaro

Call the customer service number on the back of your Part D insurance card and ask whether Mounjaro is on your plan's formulary. Have your pharmacy's name and phone number ready, because the representative may need to check your specific plan details. Ask three things: whether the drug is covered, whether your doctor needs to request prior authorization before you fill it, and what your copay or coinsurance will be.

You can also check your plan's formulary online through your insurance company's website. Most plans post a searchable list of covered drugs. Search for "tirzepatide" (Mounjaro's generic name) as well as the brand name, because some formularies list it both ways.

If your current plan does not cover Mounjaro, you can switch to a different Part D plan during the annual enrollment period (October 15 to December 7 each year). If you need Mounjaro now and your plan does not cover it, talk to your doctor about whether another diabetes drug your plan does cover might work for you, or ask about the manufacturer's savings program.

Prior Authorization and Other Plan Requirements

Many Part D plans require prior authorization before they will cover Mounjaro. This means your doctor must submit a request to the insurance company explaining why you need this drug, and the plan must approve it before your pharmacy can fill the prescription. This process usually takes a few business days, but it can delay your first dose.

Some plans also require you to try a different, cheaper diabetes drug first — usually metformin or a different GLP-1 drug like semaglutide (Ozempic). This is called a step therapy requirement. If your doctor believes Mounjaro is the right choice for you despite this requirement, they can request an exception, though this takes longer.

Ask your doctor's office to handle the prior authorization request. They have templates and know what information the insurance company needs. If the plan denies the request, your doctor can appeal, and you have the right to ask for an expedited (faster) appeal if you need the drug urgently.

What You Pay at Different Stages of the Year

Your Part D plan divides the year into four payment stages, and your costs change at each one. In the initial coverage stage (after you meet your deductible), you typically pay a fixed copay — often $35 to $75 per month for Mounjaro, depending on your plan. This is the cheapest stage.

Once you and your plan have spent a combined total of $5,850 on covered drugs in 2024 (this amount changes each year), you enter the coverage gap. In the gap, you pay a higher percentage of the drug's cost — usually 25 percent — until your out-of-pocket costs reach $8,550. At that point, you enter catastrophic coverage and pay only a small copay for the rest of the year.

Because Mounjaro is an expensive drug, you may reach the coverage gap quickly if you start it early in the year. Ask your pharmacist to estimate when you will enter the gap, so you are not surprised by higher bills in the fall.

The Manufacturer Savings Program if You Have No Part D Coverage

Eli Lilly, the company that makes Mounjaro, offers a savings program called the Mounjaro Savings Program. If you have no Part D coverage or your plan does not cover Mounjaro, you may be able to get the drug for as little as $25 per month through this program, depending on your income and insurance status.

To use the program, you do not need to enroll in advance. Your doctor writes the prescription, and you give the pharmacy a savings card (which you can print from the Eli Lilly website or ask your doctor for). The pharmacy applies the discount at checkout. The program works with most major pharmacies, including CVS, Walgreens, and Walmart.

The program has income limits. If your household income is above 400 percent of the federal poverty level, you may not may have access to. Call Eli Lilly's patient support line at 1-833-MOUNJARO (1-833-668-6527) to confirm whether you may have access to before your first prescription.

Other GLP-1 Drugs and How They Compare

Mounjaro is one of several GLP-1 drugs covered by Medicare Part D. Semaglutide (Ozempic for diabetes, Wegovy for weight loss) and dulaglutide (Trulicity) are also covered by most Part D plans, often with lower copays because they have been on the market longer. Your doctor may suggest one of these if Mounjaro is not covered by your plan or if cost is a concern.

The drugs work similarly but have different dosing schedules and side effect profiles. Mounjaro is injected once a week, as are Ozempic and Trulicity. If your plan covers multiple GLP-1 drugs, ask your doctor which one has the lowest copay and whether it would work as well for your diabetes.

If you switch drugs because of cost, your blood sugar control may change slightly at first. Your doctor will monitor your blood sugar and may adjust your dose or add another diabetes medication if needed.

What to Ask Your Doctor and When to Seek Help

Before your doctor prescribes Mounjaro, ask: "Does my insurance cover this drug, and if not, what are my other options?" and "If I need prior authorization, how long will that take?" Also ask whether the manufacturer's savings program might be cheaper than your copay, because sometimes it is.

If your insurance denies coverage or requires step therapy, ask your doctor whether they can appeal the decision or request an exception. Bring any denial letter to your appointment so your doctor can see exactly what the plan said.

If you start Mounjaro and experience severe nausea, vomiting, or signs of pancreatitis (severe upper belly pain, back pain, or vomiting), contact your doctor or go to the emergency room. These are rare but serious side effects that need when ready attention. For routine side effects like mild nausea, contact your doctor within a few days — they may adjust your dose or suggest ways to manage the symptom.

Frequently Asked Questions

Will Medicare Part B cover Mounjaro if my doctor gives it to me in the office?

No. Even if your doctor injects Mounjaro in the office, Medicare Part B will not cover it because Mounjaro is designed for self-injection at home. Part B covers injectable drugs that must be given by a healthcare provider, like insulin infusions or certain biologics. Mounjaro remains a Part D drug regardless of where it is injected.

What happens to my Mounjaro coverage if I switch Part D plans?

Your coverage may change. A new plan might cover Mounjaro with a different copay, require prior authorization, or not cover it at all. You can switch plans only during the annual enrollment period (October 15 to December 7) or if you have a may have access to life event like moving to a new state. Check the new plan's formulary before you switch to make sure Mounjaro is covered.

Can I use both my Part D copay and the manufacturer's savings card?

No. You use either your insurance copay or the manufacturer's savings card, not both. The pharmacy will explore whichever one gives you the lower price. Some people find the savings card cheaper than their copay, especially if their copay is high or they are in the coverage gap.

If I reach the coverage gap, can I stop taking Mounjaro until catastrophic coverage starts?

You should not stop taking Mounjaro without talking to your doctor first. Stopping suddenly can cause your blood sugar to rise. If cost is the problem, tell your doctor — they may switch you to a cheaper drug temporarily, adjust your dose, or help you find other ways to pay. Some programs help seniors pay for drugs in the coverage gap.

Does Medicare Advantage cover Mounjaro?

Medicare Advantage plans (Part C) include prescription drug coverage, and many cover Mounjaro, but coverage varies by plan and by region. Call your Advantage plan's customer service number to ask whether Mounjaro is on the formulary and what your copay would be. You can switch to a different Advantage plan during annual enrollment if your current plan does not cover it.