Does Medicare Cover Zepbound? The OSA Loophole and What Actually Changed

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> Reviewed by FormBlends Medical Team · Last updated May 2026 · 13 sources cited · Author: FormBlends Editorial

Key Takeaways

• Medicare Part D cannot cover Zepbound for weight loss alone due to a 2003 statutory exclusion
• The December 2024 FDA approval of Zepbound for obstructive sleep apnea created the first real Medicare coverage path
• Patients qualifying for the OSA pathway need a sleep study (AHI ≥ 15), BMI ≥ 30, and ICD-10 G47.33
• Without OSA, Medicare beneficiaries can use Lilly Direct ($499/mo) or compounded tirzepatide through a 503A pharmacy
• Legislative repeal of the weight-loss exclusion (TROA bill) has been proposed for years but has not passed

Direct answer

Medicare does not cover Zepbound for weight loss. Section 1860D-2(e)(2)(A) of the Social Security Act, enacted as part of the Medicare Modernization Act of 2003, prohibits Part D coverage of drugs used for weight loss. The December 2024 FDA approval of Zepbound for moderate-to-severe obstructive sleep apnea in adults with obesity created the first viable Medicare coverage path. CMS confirmed in 2025 that Part D plans can cover Zepbound for the OSA indication. As of May 2026, most Medicare Part D and Medicare Advantage prescription drug plans now include Zepbound on formulary for OSA with documented sleep-study evidence, prior authorization, and BMI ≥ 30.

Table of contents

1. The statutory bar on Medicare weight-loss coverage
2. What the OSA approval changed
3. How to qualify for the OSA pathway
4. Medicare Part D plan variation
5. Medicare Advantage specifics
6. Costs under Medicare for OSA-indicated Zepbound
7. The 2026 Part D out-of-pocket cap
8. If you don't qualify for OSA: alternative paths
9. The political fight over weight-loss coverage
10. FAQ
11. Sources

The statutory bar on Medicare weight-loss coverage

The Medicare Modernization Act of 2003 created the Part D prescription drug benefit. Among its exclusions: "agents when used for anorexia, weight loss, or weight gain." The exclusion was modeled on the language Medicaid uses (a different statute, separate Medicaid rules) and was drafted in the context of stimulant-class weight-loss drugs that had safety problems in the 1990s.

The exclusion is statutory, not regulatory. CMS cannot waive it. Part D plans cannot cover around it. Only Congress can change it.

The Treat and Reduce Obesity Act (TROA) has been introduced in multiple congressional sessions to remove the exclusion. The bill has accumulated bipartisan cosponsors but has not advanced past committee in any session. Cost-projection scoring by CBO has been the consistent barrier; adding GLP-1 coverage to Medicare is estimated at $35-$50 billion over a decade.

What the OSA approval changed

Drugs covered by Part D must have a non-excluded indication. The weight-loss exclusion bars coverage when the prescription is for weight loss, but does not bar coverage when the same drug is prescribed for a different FDA-approved use.

In December 2024, the FDA approved Zepbound for moderate-to-severe obstructive sleep apnea in adults with obesity. The approval was based on the SURMOUNT-OSA trial (Malhotra et al. 2024, NEJM), which showed tirzepatide reduced the apnea-hypopnea index by approximately 25 events/hour vs 5 events/hour with placebo.

CMS issued guidance in early 2025 confirming that Part D plans could include Zepbound on formulary for the OSA indication. The guidance distinguished between the prescription's clinical purpose (OSA, covered) and the drug's also-FDA-approved weight-loss indication (excluded). Plans verify the OSA purpose through PA documentation.

How to qualify for the OSA pathway

The standard requirements across Medicare Part D plans for Zepbound under the OSA indication:

• Sleep study (in-lab polysomnography or home sleep apnea test) showing apnea-hypopnea index ≥ 15 events/hour, qualifying as moderate-to-severe OSA
• BMI ≥ 30 (FDA-labeled indication is adults with obesity)
• ICD-10 G47.33 (obstructive sleep apnea, adult) on the prescription and PA submission
• Prior CPAP trial or documented intolerance/contraindication (plan-specific; not all plans require)
• Prior authorization through the Part D plan
• Reauthorization typically at 6 months with documentation of clinical benefit

The sleep study is the load-bearing document. A PA without it gets denied. If you've had a sleep study in the past 12-24 months, include it; if older, the plan may ask for a current study. Home sleep apnea tests are accepted by most plans when scored by a sleep medicine physician.

Medicare Part D plan variation

Each Medicare Part D plan sets its own formulary within CMS rules. Coverage of Zepbound for OSA has rolled out unevenly:

Plan type	OSA pathway status	Typical tier
SilverScript (CVS Caremark) standalone Part D	Covered for OSA on most plans	Tier 3-4
Aetna Medicare Advantage MA-PD	Covered for OSA on most plans	Tier 3
AARP Medicare Complete (UHC)	Covered for OSA on most plans	Tier 3
Humana Medicare	Covered for OSA on most plans	Tier 3
WellCare standalone Part D	Varies by plan year	Tier 3-4
Kaiser Medicare (regional)	Covered for OSA on most plans	Tier 3

If your specific plan doesn't list Zepbound on the formulary for OSA, request a formulary exception. CMS rules require Part D plans to consider exceptions for drugs that are not on formulary if the prescriber attests the drug is medically necessary and other formulary alternatives are not appropriate.

Medicare Advantage specifics

Medicare Advantage prescription drug plans (MA-PD) are run by private insurers under contract with CMS. The prescription drug benefit follows the same Part D rules. The MA-PD plan's formulary determines actual Zepbound coverage.

MA plans often layer additional restrictions or supports:

• Some MA plans require network sleep medicine providers for the sleep study
• Some MA plans offer chronic-care management programs that include OSA support and may streamline Zepbound PA
• Some MA plans bundle CPAP equipment supplies; the CPAP trial requirement may be met through this benefit

If you have an MA-PD and Zepbound was denied for OSA, the appeal is the same process as standalone Part D: redetermination request to the plan, then external review by an independent review entity if denied.

Costs under Medicare for OSA-indicated Zepbound

Coverage phase	Typical monthly cost
Deductible phase (annual deductible up to $590 in 2026)	Full negotiated price until met
Initial coverage phase, Tier 3 fixed copay	$47-$100
Initial coverage phase, Tier 3 coinsurance	~$200-$300
After 2026 $2,000 OOP cap reached	$0
With Extra Help (LIS)	$0-$11.40 (LIS copay rates)

The Lilly savings card does not stack with Medicare. Manufacturer coupons are excluded from federal health programs by law.

The 2026 Part D out-of-pocket cap

The Inflation Reduction Act capped Medicare Part D out-of-pocket spending at $2,000 per year starting January 1, 2025 (annual indexing applies). Once you reach the cap, additional Part D-covered prescriptions cost $0 for the rest of the year.

For Zepbound under the OSA indication, the cap matters. A patient with a $100 monthly Tier 3 copay reaches $1,200 from Zepbound alone in 12 months. Combined with other prescriptions, many beneficiaries hit the cap mid-year and pay $0 for the remainder.

The cap also allows for monthly smoothing under the Medicare Prescription Payment Plan. Beneficiaries can elect to spread the annual OOP across 12 monthly payments instead of paying spikes during the deductible phase.

If you don't qualify for OSA: alternative paths

For Medicare beneficiaries who do not have OSA or do not qualify for the OSA pathway, real options are limited:

• Lilly Direct self-pay ($499/mo): Single-dose vials shipped directly from Lilly. FDA-approved Zepbound. No insurance involved.
• Compounded tirzepatide ($199-$399/mo through 503A pharmacy): Not FDA-approved; not equivalent to Zepbound; not covered by any insurance.
• Mounjaro for T2D (if you have type 2 diabetes): Mounjaro is the same molecule as Zepbound but labeled and priced for T2D. Medicare Part D covers Mounjaro for T2D. This is a different prescription and a different process.
• Wait for legislative change: TROA or similar would remove the weight-loss exclusion. Timeline uncertain.

The most common workaround patients try (and the one that doesn't work) is asking a prescriber to write Zepbound for weight loss and bill Medicare anyway. Plans deny these claims at adjudication. Misrepresenting the indication to obtain coverage is potentially fraudulent and risks plan termination.

The political fight over weight-loss coverage

The Biden administration proposed in November 2024 a regulatory reinterpretation that would have allowed Medicare to cover AOMs for obesity treatment (not just for OSA). The proposal would have reinterpreted "weight loss" in the exclusion narrowly, treating obesity itself as the indication rather than weight loss as a goal.

The proposal generated significant industry comment and was projected to add $25-$40 billion in Medicare spending over a decade. The Trump administration withdrew the proposal in early 2025 before it took effect.

Legislative paths remain. TROA continues to be reintroduced. Bipartisan support exists in principle; CBO scoring is the barrier. Until either the statute is amended or a different administration reissues a regulatory reinterpretation, the OSA pathway is the only Medicare coverage route for Zepbound.

Contrary view: should Medicare cover weight-loss drugs?

The case against expanding Medicare AOM coverage isn't pure cost.

Three substantive arguments:

• Population effect. Roughly 40% of Medicare beneficiaries have a BMI ≥ 30. Universal AOM coverage would commit the Medicare trust fund to a significant ongoing expense without an offsetting Medicare-side savings model. Health-improvement savings would accrue to Medicaid, commercial insurance, and disability programs, not Medicare itself.
• Adherence reality. Real-world GLP-1 discontinuation rates are 50-70% at 12 months. Coverage that funds a high-discontinuation regimen produces less benefit per dollar than expected.
• Generic substitution timeline. Generic tirzepatide is unlikely before 2036. Until then, Medicare would be locked into branded pricing. Other interventions (bariatric surgery, intensive behavioral therapy) have lower long-term costs for many patients.

The case for expansion: GLP-1 medications produce clinically significant weight loss (mean 22.5% in SURMOUNT-1) that reduces cardiovascular and metabolic complications. Excluding them from Medicare creates an arbitrary care gap based on a statute drafted before the GLP-1 class existed. The OSA pathway is a partial fix that benefits only a subset of patients.

Both positions are defensible. The patient question is not which side wins the policy fight; it's how to navigate the system as it currently exists.

Decision framework

If you have Medicare and want Zepbound: Ask whether you have or might have OSA. A sleep study is the gateway document. If you have moderate-to-severe OSA and BMI ≥ 30, the coverage path exists.

If you don't have OSA: Lilly Direct ($499/mo) is the FDA-approved self-pay path. Compounded tirzepatide is cheaper but not FDA-approved.

If you have T2D: Mounjaro is covered by Medicare Part D for T2D. Same molecule, different label.

If your plan denies OSA coverage: Request a redetermination with stronger sleep-study documentation. Then external review through CMS-contracted independent review entity.

FAQ

Does Medicare cover Zepbound? Not for weight loss. For OSA in adults with obesity, yes (subject to plan formulary and PA).

Why the difference? The Medicare Modernization Act of 2003 statutorily excludes weight-loss drugs from Part D. The 2024 FDA OSA approval created a non-weight-loss indication that is not excluded.

What do I need to qualify? Sleep study showing AHI ≥ 15, BMI ≥ 30, ICD-10 G47.33, prior authorization through your Part D plan.

What does Zepbound cost on Medicare for OSA? $47-$100 Tier 3 copay typically; full price during the deductible phase; $0 after reaching the 2026 $2,000 OOP cap.

Can I use the Lilly savings card? No. Manufacturer copay cards are not permitted with Medicare.

What if my plan does not list Zepbound on its formulary? Request a formulary exception through your prescriber.

Will Medicare ever cover Zepbound for weight loss? Only with statutory change. Bills have been proposed but not passed.

What if I have T2D? Mounjaro (same molecule, different label) is covered by Medicare Part D for T2D.

Sources

1. Malhotra A et al. Tirzepatide for the Treatment of Obstructive Sleep Apnea and Obesity. NEJM. 2024.
2. Jastreboff AM et al. Tirzepatide Once Weekly for the Treatment of Obesity. NEJM. 2022.
3. Social Security Act, Section 1860D-2(e)(2)(A). Drug exclusions from Part D.
4. Medicare Modernization Act of 2003. Public Law 108-173.
5. Centers for Medicare & Medicaid Services. Part D Manual, Chapter 6. Updated 2025.
6. CMS. Guidance on Part D coverage of tirzepatide for OSA. 2025.
7. FDA. Approval of Zepbound for obstructive sleep apnea. December 2024.
8. Inflation Reduction Act of 2022. Public Law 117-169. Part D out-of-pocket cap provisions.
9. Congressional Budget Office. Cost estimate of expanded Medicare AOM coverage. 2024.
10. Treat and Reduce Obesity Act. Legislative history, 117th-119th Congresses.
11. Biden administration HHS Notice of Proposed Rulemaking. AOM coverage proposal. November 2024.
12. Trump administration HHS. Withdrawal of proposed AOM coverage rule. 2025.
13. Eli Lilly. LillyDirect self-pay program. Accessed May 2026.

Footer disclaimers

Platform Disclaimer. FormBlends offers educational information about Medicare coverage rules. We are not a Medicare plan, a Part D sponsor, or a federally authorized Medicare counselor. For Medicare-specific decisions, consult your plan documents, 1-800-MEDICARE, or your local State Health Insurance Assistance Program (SHIP).

Compounded Medication Notice. Compounded tirzepatide prepared by 503A pharmacies is not FDA-approved and is not therapeutically equivalent to Zepbound. Medicare does not cover compounded medications under Part D, and Lilly's savings programs do not apply to compounded products.

Results Disclaimer. Cost and coverage examples are illustrative and reflect the 2026 Medicare benefit structure as currently legislated. Annual changes occur each January. Your specific plan, deductible position, and OOP cap status will produce different individual results.

Trademark Notice. Zepbound and Mounjaro are registered trademarks of Eli Lilly and Company. Medicare is a federal health insurance program. SilverScript, AARP Medicare Complete, Humana Medicare, Aetna Medicare, WellCare, and Kaiser Medicare are registered trademarks of their respective owners. FormBlends has no affiliation with CMS, the Medicare program, or any Medicare plan.