What to Do If Your GLP-1 Prior Authorization Is Denied
A denial is a starting point, not a final answer. Here's the Medicare appeal process step by step — with timelines and sample language.
By Alex Carter, Medicare benefits specialist · Published June 26, 2026 · Reviewed June 26, 2026
Getting a denial letter for your GLP-1 prior authorization is frustrating, but it is not the end of the road. Medicare gives every beneficiary a formal, multi-level appeals process, and a large share of denials are overturned when the right documentation is submitted. The most important thing to know is this: a denial is a starting point, not a final answer. Here is exactly what to do, step by step.
First, find out why it was denied
Your plan must send a written notice explaining the reason for the denial. Read it carefully — the fix depends entirely on the reason. The most common reasons are a diagnosis code that does not match a covered indication, missing lab values or clinical notes, a step-therapy requirement (the plan wants you to try a different drug first), or a quantity or dose outside the plan's limits. Knowing the specific reason tells you and your prescriber what to correct.
The Medicare appeal process, step by step
- Request a redetermination (Level 1). Ask your Part D plan to review the denial. You generally have 60 days from the date of the denial notice to file. Include a letter of medical necessity from your prescriber.
- Independent review (Level 2). If the plan upholds the denial, an outside organization — the Independent Review Entity — re-examines your case.
- Administrative Law Judge (Level 3). If the dollar amount in dispute meets the threshold, you can request a hearing before a judge.
- Medicare Appeals Council (Level 4) and finally federal court (Level 5) if the amount qualifies.
Source: CMS.gov — Part D coverage determinations, appeals, and grievances. Timeframes can change; confirm current rules with your plan.
Standard vs. expedited timelines
For a standard redetermination, your plan must respond within 7 calendar days. If waiting could seriously harm your health, you or your prescriber can request an expedited review, which must be decided within 72 hours. Ask your prescriber to mark the request as expedited and explain the health risk of delay. Keep copies of every letter and note the date you filed — the clock starts from the denial notice.
Sample appeal language
You can adapt wording like this for the patient portion of a redetermination request (your prescriber will add the clinical detail):
"I am requesting a redetermination of the denial dated [date] for [drug name]. My prescriber has determined this medication is medically necessary to treat my [qualifying condition]. I have attached a letter of medical necessity and supporting records, including [lab values / prior treatments tried / diagnosis documentation]. Please reconsider coverage under my Part D plan."
A strong letter of medical necessity from your prescriber is the single most powerful part of an appeal. It should state your diagnosis, the clinical evidence, which other treatments you have tried or why they are not appropriate, and why this specific GLP-1 is needed.
Tips that improve your odds
- Act quickly — do not let the 60-day window lapse.
- Work hand-in-hand with your prescriber's office; they file most appeals routinely.
- Attach every relevant lab result and chart note the first time.
- If step therapy is the issue, document the drugs you already tried and any side effects.
- Keep a dated log of every call and letter.
For background on how the original request works, see our prior authorization guide. If your appeal ultimately fails, our other coverage options page outlines Medicaid, employer, and cash-pay alternatives.
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