Getting a continuous glucose monitor (CGM) prescription typically starts with your primary care doctor or endocrinologist, and the process is more straightforward than most people expect. If you use insulin or have trouble managing your blood sugar, you likely qualify. Even if you don’t have diabetes, there are now over-the-counter options that skip the prescription entirely. Here’s what you need to know about each path.
Who Qualifies for a Prescription CGM
CGMs like the FreeStyle Libre and Dexcom G7 are FDA-cleared for managing diabetes in people age 4 and older. The strongest candidates for a prescription are people who take insulin, use other glucose-lowering medications, or aren’t meeting their blood sugar targets (generally an A1c of 8.0% or higher). A history of problematic low blood sugar episodes also qualifies you, even if your A1c looks fine on paper.
Pregnancy, dialysis, and critical illness are listed as contraindications for some systems, so your doctor may need to consider alternatives in those situations.
What to Bring to Your Appointment
Your doctor needs to justify medical necessity, so walk in prepared. The most useful things to bring or discuss are your most recent A1c result, a log of your blood sugar readings (especially any lows below 54 mg/dL), your current medication regimen, and any instances where low blood sugar required someone else to help you. If you’ve been checking your blood sugar with finger sticks at least three times a day and still struggling with control, say so explicitly. These details directly map to the criteria insurers use to approve coverage.
You don’t need to convince your doctor that CGMs exist or are useful. Most primary care physicians and endocrinologists prescribe them routinely. Frame the conversation around your specific blood sugar challenges and let the clinical picture speak for itself.
How Insurance Coverage Works
How your CGM gets covered depends on whether your insurance processes it as a pharmacy benefit or as durable medical equipment (DME). This distinction matters more than most people realize, because it affects how long you wait, how much paperwork your doctor does, and what your out-of-pocket cost looks like.
Under the DME route, your doctor’s office submits a prior authorization with detailed documentation: blood glucose records, history of complications, and other clinical information. A specialized DME supplier then ships your sensors and provides training and product support. This process can take days to weeks.
The pharmacy route is faster. Your doctor fills out a simplified one-page form documenting medical need, and you pick up your sensors at a retail pharmacy, sometimes the same day. The trade-off is that pharmacies generally offer less hands-on training and support than DME suppliers. If you’re new to CGMs, you may need to rely more on the manufacturer’s app tutorials and customer service.
Insurance plans are increasingly shifting CGM coverage to pharmacy benefits specifically to reduce administrative burden and speed up access. Ask your insurer which channel they use so your doctor sends the prescription to the right place.
Medicare and Medicaid Requirements
Medicare covers CGMs if you take insulin or have a documented history of problematic hypoglycemia. You also need to have received adequate training (or your caregiver has) on how to use the device as prescribed. That’s it. Medicare simplified its criteria in recent years, dropping the old requirement that patients test their blood sugar four times a day with finger sticks.
Medicaid coverage varies by state and tends to be stricter. Colorado’s Medicaid program, for example, requires that you self-monitor glucose at least three times daily, take three or more insulin injections per day (or use an insulin pump), and need frequent adjustments to your insulin regimen. Your state may have similar or different thresholds, so check with your Medicaid plan directly or ask your doctor’s office to verify before the prescription is written.
Lowering Your Out-of-Pocket Cost
Both major CGM manufacturers offer savings programs that can cut costs significantly. Dexcom’s pharmacy savings program is available to anyone with a prescription, reducing the retail cash price by over 50%. You don’t need commercial insurance to use it, but you do need to opt out of insurance coverage or any other coupon to apply it. Close to 90% of people with type 1 diabetes on commercial insurance already have Dexcom coverage, and roughly half of people not on insulin are covered as well.
Abbott’s FreeStyle Libre copay card is available to commercially insured and uninsured patients, but not to anyone on Medicare, Medicaid, or other government programs. Abbott positions Libre as the lower-cost option based on list price comparisons, though your actual cost depends on your specific insurance plan. If you’re uninsured, ask your pharmacist to run both manufacturers’ discount cards to see which nets you the lower price.
The Over-the-Counter Option
If you don’t use insulin, you may not need a prescription at all. The FDA cleared the Dexcom Stelo as the first over-the-counter CGM for adults 18 and older who don’t take insulin. It’s designed for people managing diabetes with oral medications or anyone without diabetes who wants to see how food and exercise affect their blood sugar in real time.
The Stelo uses a wearable sensor paired with a smartphone app, just like prescription CGMs. The key limitation: it doesn’t include low blood sugar alerts, so it’s not appropriate for anyone with a history of problematic hypoglycemia. If you’re primarily curious about metabolic health and want data without navigating insurance, this is the simplest path. You order it directly and start wearing it.
If Your Doctor Says No
Some doctors are hesitant to prescribe CGMs for patients with type 2 diabetes who aren’t on insulin, or for people with prediabetes. If your doctor declines, you have a few options. First, ask specifically what criteria you’re not meeting and whether any changes to your monitoring routine (like documenting more finger-stick readings) would strengthen the case. Second, request a referral to an endocrinologist, who prescribes CGMs more frequently and may be more familiar with navigating insurance approvals. Third, if you don’t use insulin and your goal is metabolic insight rather than managing a dangerous condition, the over-the-counter Stelo may be the more practical route anyway, since it sidesteps the prescription and insurance process entirely.
For people who do qualify clinically but face insurance pushback, your doctor’s office can file an appeal. The most common reason for denial is incomplete documentation, not ineligibility, so making sure your records include specific blood sugar values, A1c trends, and medication history gives the appeal the best chance of success.