Which BMI counts? The one you started with.
Here's the rule that surprises almost everyone: the Bridge assesses the clinical criteria at the time GLP-1 therapy starts. If you're already taking one, your BMI from the day you began — not today's — is the number that matters. For people who've been paying out of pocket and losing weight, that's very good news.
Why the rule exists
Without it, the program would punish success: lose 40 pounds on self-pay Wegovy, drop below the BMI threshold, and suddenly you'd be "ineligible" for coverage of the medication that got you there. CMS's provider guidance instead anchors the criteria to therapy initiation — including for people who started before the Bridge launched or before they joined Medicare.
What this means in practice
Say you started Zepbound eighteen months ago at a BMI of 36 and you're at 29 today. For the Bridge criteria, you're a BMI-35-pathway candidate — provided your starting number is documented. The work is finding that documentation: old clinic notes, your patient portal's weight history, even LillyDirect or NovoCare records that establish when you started. Your doctor's chart is the strongest source, so if your weight was recorded around the time you began, you're in good shape.
What to gather
- The date you started GLP-1 therapy (approximately is fine to start the conversation)
- Your weight or BMI around that date, with whatever records support it
- Your medication and dose history since then
- Your current weight, for context
How the screener handles it
The free screener asks for both your current weight and your starting weight, calculates both BMIs, uses the right one for the criteria comparison, and labels clearly which one it used — so your doctor sees the logic, not just a number. If you can't find your starting weight, the screener flags it as the thing for your doctor to pull from your chart, which is often the fastest resolution anyway.
Frequently asked questions
My BMI is below 27 now after losing weight. Am I out?
Not necessarily — if your BMI when you started therapy met a pathway, that's the number the criteria assess. Document it.
What if I don't know my starting weight?
Check old clinic notes, your portal, or pharmacy/LillyDirect/NovoCare records — or ask your doctor's office to check the chart.
Does a home-scale weight count as proof?
Ask your clinician — chart records are strongest, and your doctor decides what supports the prior authorization.
Sources and review status: Content reviewed June 12, 2026, based on published CMS materials including the prescriber fact sheet (CMS Product No. 12235). Check current CMS materials: CMS Bridge overview, beneficiary information, provider information.