What Medicare covers for weight loss drugs

Medicare Part D (prescription drug coverage) covers some weight loss medications, but not all of them. The drugs that are covered depend on your specific Part D plan — each plan makes its own list of covered medications, called a formulary. Two medications appear on most plans: phentermine, a short-term appetite suppressant you take for up to 12 weeks, and orlistat, which reduces how much fat your body absorbs from food. Newer drugs like semaglutide (Ozempic, Wegovy) and tirzepatide (Zepbound, Mounjaro) are covered by some plans but not others, and coverage rules change year to year.

Medicare Part B does not cover weight loss drugs as a standalone treatment. Part B covers doctor visits and some procedures, but prescription medications for weight loss fall under Part D. If you do not have Part D coverage, you would pay the full price out of pocket, which can be several hundred dollars per month for newer medications.

Key Takeaways

  • Phentermine and orlistat appear on most Medicare Part D formularies, though your out-of-pocket cost depends on your specific plan.
  • Newer weight loss drugs like semaglutide and tirzepatide are covered by some Part D plans but not all, and you need to check your plan's formulary before your doctor prescribes.
  • Medicare requires your doctor to document that weight loss is medically necessary — usually because you have obesity-related conditions like diabetes or heart disease — before Part D will pay.
  • Your Part D plan may require prior authorization, meaning your doctor must get approval from the insurance company before you fill the prescription.
  • Coverage and cost-sharing rules reset every January 1st, so a drug covered this year may move to a higher tier or be removed next year.

How to learn about your plan covers a specific drug

The fastest way is to check your plan's formulary online. Log into your Medicare.gov account, go to "My Health Care", and select your Part D plan. You can search by drug name and see whether it is covered, what tier it is on (which determines your copay), and whether prior authorization is required. If you do not have online access, call the customer service number on the back of your Part D card.

When you call or search, have the drug's full name ready — for example, "semaglutide" rather than just "Ozempic", because the same medication can have multiple brand names. Ask three specific things: whether the drug is on the formulary, what your copay or coinsurance will be, and whether your doctor needs to get prior authorization before you can fill it. If the drug is not covered, ask whether there are similar medications on the formulary that your doctor might prescribe instead.

Prior authorization and medical necessity requirements

Most Medicare Part D plans require prior authorization for weight loss drugs, especially the newer ones. This means your doctor must submit paperwork to the insurance company explaining why you need the medication. The insurance company then decides whether to approve it based on your medical history. This process usually takes 3 to 5 business days, though it can be faster if your doctor's office submits it electronically.

Medicare requires documentation that weight loss is medically necessary for you specifically. This typically means you have a condition related to obesity — such as type 2 diabetes, high blood pressure, heart disease, or sleep apnea — and your doctor believes the medication will help manage that condition. straightforward being overweight is usually not enough. Your doctor's notes need to show your current weight, your body mass index (BMI), and what health problems the weight loss would help treat.

If your plan denies the prior authorization request, you have the right to appeal. Your doctor can submit additional medical information, or you can file a formal appeal with your Part D plan. The appeals process takes longer — usually 30 to 60 days — so ask your doctor whether they recommend appealing or trying a different medication while the appeal is pending.

Cost differences between weight loss drugs on Medicare

Your out-of-pocket cost depends on which tier the drug is on in your plan's formulary. Tier 1 drugs (usually generic medications like phentermine) typically have the lowest copay, often $5 to $15 per month. Tier 2 and Tier 3 drugs (brand-name and newer medications) usually cost $25 to $75 per month. Tier 4 and Tier 5 drugs (the newest or most expensive options) can cost $100 to $300 or more per month, depending on your plan.

Some plans use coinsurance instead of a copay, meaning you pay a percentage of the drug's cost — for example, 25 percent — rather than a flat amount. Once you reach your plan's deductible and hit the coverage gap (also called the "donut hole"), your costs change again. In the coverage gap, you pay a higher percentage of the drug's cost until you reach your out-of-pocket maximum, at which point Medicare pays most of the cost for the rest of the year.

If the cost is too high, talk to your doctor about whether a generic or lower-tier option might work for you. Phentermine is inexpensive and effective for short-term use. Orlistat is available over the counter without a prescription, though prescription-strength orlistat may be covered at a lower cost than buying it yourself.

What happens during the coverage gap

Once you and your plan have paid a combined total of $5,050 toward your prescriptions in 2024 (this amount changes each year), you enter the coverage gap. In the gap, you pay a larger share of the cost — currently 25 percent of the drug's price for most medications. You stay in the gap until your out-of-pocket spending reaches $8,550 (also adjusted yearly), at which point catastrophic coverage kicks in and Medicare pays most of the remaining cost.

Weight loss drugs are expensive, so if you start one early in the year, you may hit the coverage gap before the year ends. Ask your pharmacist to estimate when you might reach the gap based on your prescription refills. Some people choose to pause their medication temporarily to avoid the higher costs in the gap, though you should discuss this with your doctor first.

Switching plans or appealing a denial

If your current Part D plan does not cover the weight loss drug your doctor recommends, you have options. During the Annual Enrollment Period (October 15 to December 7 each year), you can switch to a different Part D plan that does cover it. Use the Medicare Plan Finder tool on Medicare.gov to compare plans and see which ones include your medication on their formulary.

If you are outside the enrollment period and your plan recently denied coverage for a drug you were already taking, you may be able to request a coverage exception. Your doctor submits a statement explaining why this specific drug is medically necessary for you and why alternatives would not work. The plan then decides whether to make an exception to their formulary rules. This is different from prior authorization — it is asking the plan to cover something they normally do not.

If your plan denies a coverage exception, you can file a formal appeal. The appeals process has multiple levels, and at each level you have the right to present new medical information. Many people succeed on appeal, especially if their doctor provides strong documentation of medical need.

Over-the-counter weight loss options and Medicare

Medicare Part D does not cover over-the-counter medications, including over-the-counter orlistat (Alli, Xenical). If your plan's copay for prescription orlistat is high, you might save money by buying the over-the-counter version at a pharmacy or online. The dosage is lower than prescription strength, but it may still be effective for you.

Other over-the-counter weight loss products — such as supplements, appetite suppressants, or meal replacement shakes — are not covered by Medicare at all. If your doctor recommends any of these, you would pay the full cost yourself. Talk to your doctor before starting any over-the-counter product, because some can interact with other medications or affect chronic conditions.

Frequently Asked Questions

Does Medicare Part B cover weight loss drugs?

No. Part B covers doctor visits, lab work, and some procedures, but not prescription medications for weight loss. Weight loss drugs fall under Part D (prescription drug coverage). If you do not have Part D, you would pay the full price out of pocket.

Will my doctor's office help with prior authorization?

Yes, most doctors' offices handle prior authorization requests as part of their normal process. When your doctor prescribes a weight loss medication, their staff usually submits the paperwork to your Part D plan. Call your doctor's office and ask them to submit it — you should not have to do this yourself.

What if my weight loss drug is removed from my plan's formulary next year?

During the Annual Enrollment Period (October 15 to December 7), you can switch to a different Part D plan that covers it. You can also ask your doctor whether a similar medication on your current plan's formulary might work for you. Some plans grandfather in people already taking a drug, meaning they let you keep taking it even after removing it from the formulary for new users.

Can I get a weight loss drug covered if I only have Original Medicare without Part D?

No, but you can enroll in a Part D plan during the Annual Enrollment Period or if you have a may have access to life event. If you enroll outside the regular enrollment period without a may have access to event, you may pay a late enrollment penalty. Contact Medicare at 1-800-MEDICARE to discuss your options.

How much will semaglutide or tirzepatide cost me on Medicare?

It depends on your specific Part D plan. Some plans cover these drugs with a copay of $50 to $150 per month. Others do not cover them at all, or require prior authorization and higher copays. Check your plan's formulary or call your plan's customer service number to find out your exact cost.