Medicare's Coverage of Weight Loss Drugs

Medicare Part D (prescription drug coverage) covers some weight loss medications, but not all of them, and coverage rules differ between plans. The drugs Medicare is most likely to cover are those originally approved by the FDA for diabetes or heart disease — like semaglutide (Ozempic, Wegovy) and tirzepatide (Zepbound, Mounjaro) — because they treat multiple conditions. Newer drugs marketed primarily for weight loss often face higher barriers: your plan may require you to try and fail cheaper alternatives first, or may not cover them at all.

Coverage also depends on your specific Part D plan. Each plan's formulary (the list of drugs it covers) is different, and each sets its own rules about prior authorization, step therapy, and out-of-pocket costs. A drug covered under one plan may be excluded from another, or covered only at a higher tier with a larger copay. You need to check your own plan's formulary, not a general list.

Key Takeaways

  • Medicare Part D covers some weight loss medications, but which ones depends entirely on your specific plan's formulary.
  • Semaglutide and tirzepatide are more likely to be covered because they treat diabetes and heart disease, not just weight loss.
  • Your plan may require step therapy — meaning you must try and fail a cheaper drug first before the plan will pay for a newer one.
  • You can check your plan's coverage by logging into your plan's website, calling the plan directly, or using Medicare.gov's Plan Finder tool.
  • If your plan does not cover a drug your doctor prescribes, you can ask your doctor to request an exception, or switch plans during the annual open enrollment period.

How to Check What Your Plan Covers

The fastest way is to log into your Part D plan's website and search the formulary by drug name. Look for the specific medication your doctor recommended — not just the generic class. For example, semaglutide has multiple brand names (Ozempic for diabetes, Wegovy for weight loss), and your plan may cover one but not the other, or cover them at different tiers.

If you do not have your plan's website handy, call the customer service number on the back of your Medicare card. Have your doctor's name and the exact drug name ready. Ask three things: Is it covered? What tier is it on (tier 1 is usually cheapest, tier 5 most expensive)? And does the plan require prior authorization or step therapy?

You can also use Medicare.gov's Plan Finder tool. Go to Medicare.gov, select "Find Care Providers & Suppliers", then search for your plan and drug. This tool shows you what the plan covers and what you will pay out of pocket, though the information can lag by a few weeks.

Step Therapy and Prior Authorization

Step therapy means your plan will only pay for a newer or more expensive drug if you have already tried a cheaper one first and it did not work for you. For weight loss medications, this often means your plan requires you to try metformin (a diabetes drug that costs very little) or orlistat (an older weight loss drug available over the counter) before it will cover semaglutide or tirzepatide.

Prior authorization means your doctor must submit a request to your plan before you fill the prescription, explaining why the drug is medically necessary. The plan then approves or denies the request. This can add one to three days to the process. Some plans require both step therapy and prior authorization for the same drug.

Your doctor's office usually handles these requests, but it is worth asking them directly: "Will my plan require prior authorization or step therapy for this drug?" If the answer is yes, ask how long it typically takes and whether there is a faster route if the first drug does not work.

What Weight Loss Drugs Are Most Likely to Be Covered

Semaglutide and tirzepatide have the broadest coverage because they were originally approved to treat type 2 diabetes and heart disease. Medicare plans are more willing to cover drugs for multiple conditions, especially serious ones. When these drugs are prescribed for weight loss in someone without diabetes, some plans still cover them — but may require prior authorization or step therapy.

Phentermine, an older stimulant-based weight loss drug, is covered by many Part D plans because it is inexpensive and has been in use for decades. However, it is approved only for short-term use (12 weeks or less) and is not suitable for everyone.

Newer drugs marketed primarily for weight loss — like orlistat (Xenical) — may be covered, but often at a higher tier or with step therapy. Some plans do not cover them at all. Drugs still in clinical trials or very recently approved are unlikely to be on any formulary yet.

Out-of-Pocket Costs and Deductibles

Your actual cost depends on your plan's deductible, the drug's tier, and whether you have reached the coverage gap (the "donut hole"). Most Part D plans have a deductible you pay before the plan starts paying — this ranges from zero to several hundred dollars depending on the plan. Once you meet the deductible, you pay a copay or coinsurance for each prescription.

Weight loss medications are typically tier 3 or higher, meaning your copay is likely to be $35 to $75 per month or more, depending on your plan. If you reach the coverage gap (which happens after you and your plan have spent a certain amount together), your costs jump significantly until you reach catastrophic coverage later in the year.

Some plans offer lower copays for generic drugs or drugs on a preferred list. If your plan covers semaglutide but charges a high copay, ask your doctor whether a different drug on the plan's preferred list might work for you.

What to Do If Your Plan Does Not Cover the Drug

If your doctor prescribes a weight loss medication and your plan does not cover it, you have three options. First, ask your doctor to submit a coverage exception request (sometimes called an appeal). The doctor explains to the plan why this specific drug is medically necessary for you and why alternatives will not work. Plans approve some exceptions, especially if the doctor documents that you have already tried the step-therapy drug and it failed.

Second, you can pay out of pocket. Many weight loss medications cost $200 to $500 per month without insurance. Some manufacturers offer patient information programs that reduce the cost if your income is below a certain threshold — ask your doctor or pharmacist whether the drug maker offers one.

Third, you can switch to a different Part D plan during the annual open enrollment period (October 15 to December 7 each year). Use Medicare.gov's Plan Finder to search for plans that cover the drug you need. You can switch plans once per year during this window. If you have a may have access to life event (like moving to a new state or losing other coverage), you may be able to switch outside this window.

Medicare Advantage Plans and Weight Loss Medication

If you have a Medicare Advantage plan (Part C) instead of Original Medicare with Part D, your coverage for weight loss medications works differently. Medicare Advantage plans are required to cover at least as much as Original Medicare, but each plan sets its own formulary and rules. Some Advantage plans cover weight loss drugs more generously than Part D plans; others cover them less.

Check your Advantage plan's formulary the same way you would check a Part D plan's — through the plan's website or by calling the number on your card. If your Advantage plan does not cover the drug your doctor wants to prescribe, you can request an exception or switch to a different Advantage plan (or to Original Medicare with Part D) during open enrollment.

Frequently Asked Questions

Does Medicare cover Ozempic or Wegovy for weight loss?

It depends on your specific Part D plan. Both brand names contain semaglutide, but some plans cover Ozempic (the diabetes version) and not Wegovy (the weight loss version), or cover them at different tiers. Check your plan's formulary or call your plan to find out. Your doctor may also need to request prior authorization.

What if I cannot afford the copay for my weight loss medication?

Ask your doctor or pharmacist whether the drug manufacturer offers a patient information program — many do, and some reduce the cost to zero if your income is below a certain level. You can also ask your doctor whether a cheaper alternative on your plan's formulary might work for you, or whether they can request a coverage exception to lower your copay.

Can I switch Medicare plans to get coverage for a weight loss drug?

Yes, during the annual open enrollment period (October 15 to December 7). Use Medicare.gov's Plan Finder to search for Part D plans or Medicare Advantage plans that cover the specific drug you need. You can switch once per year during this window. If you have a may have access to life event, you may be able to switch outside this period.

Does Original Medicare Part A or B cover weight loss medication?

No. Part A covers hospital stays and Part B covers doctor visits and some procedures. Prescription drugs are covered only by Part D (standalone prescription plans) or through Medicare Advantage plans that include drug coverage. You must have one of these to get coverage for weight loss medications.

What happens if my doctor prescribes a weight loss drug that my plan does not cover?

Ask your doctor to submit a coverage exception request to your plan, explaining why this drug is necessary for you and why alternatives will not work. If the plan denies the exception, you can pay out of pocket, look for a manufacturer information program, or switch to a different plan during open enrollment.