Medicare's Coverage of Weight Loss Medications

Medicare Part D (prescription drug coverage) covers some weight loss drugs, but not all of them, and coverage rules changed in 2024 in ways that affect what you pay in 2025. The main change: Medicare can now cover GLP-1 drugs like semaglutide (Ozempic, Wegovy) and tirzepatide (Zepbound, Mounjaro) for weight loss in people with obesity and certain other health conditions. However, your specific plan decides whether to include these drugs on its formulary — the list of medications it will pay for — so you need to check your own plan's details, not just know that Medicare allows it.

Coverage varies widely by plan. Some plans cover these drugs with a copay or coinsurance. Others exclude them entirely or require you to try and fail other weight loss approaches first. A few plans cover them only for diabetes (where they were already covered) and not for weight loss alone. Your plan's formulary can change year to year, so even if your drug was covered in 2024, you should verify it is still covered in 2025.

Key Takeaways

  • Medicare Part D plans may cover GLP-1 weight loss drugs like semaglutide and tirzepatide starting in 2025, but each plan decides whether to include them on its formulary.
  • You must check your specific plan's formulary and call the plan directly to learn your copay, any prior authorization requirements, and whether the drug is covered for weight loss or only for diabetes.
  • Plans may require step therapy, meaning you must try other weight loss methods or medications first before the plan will pay for a GLP-1 drug.
  • If your plan does not cover the drug you need, you can switch to a different Part D plan during the Annual Enrollment Period (October 15 to December 7 each year).
  • Original Medicare (Part A and B alone) does not cover weight loss drugs; you must have Part D or a Medicare Advantage plan with drug coverage.

How to Check What Your Plan Covers

Start by finding your plan's formulary on Medicare.gov or your plan's website. The formulary is a searchable list of covered drugs. Search for the specific drug name — semaglutide, tirzepatide, phentermine, or whatever your doctor recommended — and note whether it appears and what tier it is on (tier 1 is usually cheapest, tier 4 or 5 is most expensive).

Then call your plan's customer service number (on the back of your Medicare card) and ask three things: Is this drug covered for weight loss, or only for diabetes? Do you need prior authorization or step therapy? What is my copay or coinsurance? Do not rely on the website alone — formularies change, and the person on the phone can tell you about restrictions the website does not list clearly.

If the drug is not on your formulary, ask whether your plan covers any weight loss drugs at all. Some plans cover older medications like phentermine or orlistat. If your plan covers nothing you need, you have the right to switch plans during the Annual Enrollment Period.

Prior Authorization and Step Therapy Requirements

Many plans require prior authorization before they will pay for a GLP-1 drug. This means your doctor must submit paperwork to the plan explaining why you need the drug, and the plan must approve it before you fill the prescription. This can add one to three weeks to the process, so your doctor should start this conversation early if you are considering one of these drugs.

Some plans also use step therapy, which means the plan will only pay for a GLP-1 drug if you have already tried and failed other weight loss methods — such as a supervised diet program, another medication, or behavioral counseling. If your plan has step therapy, you will need to document that you completed those steps before the plan will cover the GLP-1 drug.

Ask your doctor's office to check with your plan about these requirements before your first appointment to discuss weight loss treatment. This saves time and prevents surprises at the pharmacy.

What These Drugs Cost Without Insurance

If your plan does not cover the drug or you have not met your deductible, the out-of-pocket cost is high. Semaglutide (Wegovy) costs roughly $900 to $1,300 per month at retail price. Tirzepatide (Zepbound) costs roughly $1,000 to $1,500 per month. Phentermine, an older drug, costs $20 to $100 per month. Orlistat (Xenical) costs $100 to $200 per month.

Some manufacturers offer patient information programs that reduce the cost if you meet income requirements. Ask your doctor or pharmacist whether the drug you are considering has a program. These programs are separate from Medicare and do not count toward your Part D deductible or out-of-pocket maximum.

Medicare Advantage Plans and Weight Loss Drugs

If you have a Medicare Advantage plan (Part C), it must include Part D drug coverage or a separate prescription drug plan. The same rules explore: check your plan's formulary, call to confirm coverage, and ask about prior authorization. Medicare Advantage plans sometimes have different formularies than standalone Part D plans, so you cannot assume a drug is covered just because another plan covers it.

Some Medicare Advantage plans also cover weight loss programs or counseling as a supplemental benefit. Ask your plan whether it covers nutrition counseling, gym memberships, or behavioral health services related to weight management. These benefits vary widely and are not standard across all plans.

Switching Plans if Your Drug Is Not Covered

If your current plan does not cover the weight loss drug your doctor recommended, you can switch to a different Part D plan or Medicare Advantage plan during the Annual Enrollment Period, which runs from October 15 to December 7 each year. The new coverage takes effect January 1.

Use the Medicare Plan Finder tool on Medicare.gov to search for plans that cover your specific drug. Enter the drug name and your zip code, and the tool will show you which plans in your area include it and what your copay would be. Compare plans on price, but also on other drugs you take — switching to save money on one drug can cost you more on others.

If you miss the Annual Enrollment Period, you may still be able to switch if you have a may have access to life event, such as moving to a new state, losing other insurance, or having a significant change in income. Call 1-800-MEDICARE to ask whether your situation qualifies.

Questions to Ask Your Doctor

Before you and your doctor decide on a weight loss drug, ask: What is the goal of this treatment — to reach a certain weight, to improve a specific health condition like diabetes or heart disease, or both? How long would I take this drug — weeks, months, or years? What happens if I stop taking it? What are the side effects, and which ones mean I should call you right away?

Also ask: Do you know whether my Medicare plan covers this drug? If not, can you help me check? Are there other drugs my plan might cover instead? If my plan requires prior authorization or step therapy, can your office handle that paperwork?

If your doctor recommends a drug your plan does not cover, ask whether there is an alternative your plan does cover, or whether the plan's step therapy requirement is something you are willing to go through first.

Frequently Asked Questions

Does Original Medicare cover weight loss drugs?

No. Original Medicare (Part A and Part B) does not cover weight loss medications. You must have Part D prescription drug coverage or a Medicare Advantage plan with drug benefits. If you have Original Medicare without Part D, you can enroll in a standalone Part D plan during the Annual Enrollment Period or within 63 days of losing other creditable coverage.

What if I cannot afford the copay for a weight loss drug?

Ask your doctor or pharmacist about manufacturer patient information programs — these are free programs run by drug makers that reduce or eliminate the cost if you meet income limits. You can also ask your plan about generic alternatives or older drugs that may have lower copays. Some community health centers offer sliding-scale fees for weight loss counseling and medication management.

Can I use a GoodRx coupon or discount card instead of my Medicare coverage?

You should not. Using a discount card instead of your Medicare coverage can affect your Part D deductible and out-of-pocket maximum calculations, and may cost you more in the long run. Always use your Medicare card at the pharmacy. If the copay is too high, talk to your doctor or plan about other options.

What if my plan covers the drug but requires step therapy?

Step therapy means your plan will only pay for the GLP-1 drug after you have tried other approaches first — such as a diet program, another medication, or counseling. Your doctor can request an exception if they believe step therapy is not appropriate for you, but this requires paperwork and takes time. Ask your plan what steps it requires and whether your doctor thinks you should try them or request an exception.

Can I switch Medicare plans in the middle of the year to get a weight loss drug?

Not unless you have a may have access to life event. The Annual Enrollment Period is October 15 to December 7. If you need a drug urgently and your plan does not cover it, call 1-800-MEDICARE to ask whether your situation qualifies for a special enrollment period.