The Monitoring Landscape Has Shifted
Walk into any pharmacy in Phoenix or a diabetes clinic in Boston, and you will notice something different from just a few years ago. The row of traditional fingerstick meters now shares shelf space with sleek, wearable sensors. The conversation around blood sugar has moved from "test before meals" to "understand your patterns."
This shift matters because the old approach left enormous gaps. A person could test fasting glucose every morning, see a decent number, and still have dangerous spikes after lunch. They could check before bed and miss a nighttime low that lasted hours. Point-in-time readings gave a snapshot when what people needed was a movie.
The American Diabetes Association now emphasizes a metric called Time in Range (TIR) alongside the familiar HbA1c. TIR measures the percentage of the day your glucose stays within a target window—typically 70 to 180 mg/dL. The goal for most adults is to stay in range at least 70% of the time, which translates to nearly 17 hours each day. Two people can have the same A1c but dramatically different glucose stability. One might cruise along smoothly while the other rides a rollercoaster of highs and lows. The A1c alone will not tell you which one you are.
That is where continuous glucose monitors have changed the game.
Choosing a Monitoring Approach
Not everyone needs the same tools. A 28-year-old with Type 1 diabetes managing insulin daily has very different requirements than a 65-year-old with Type 2 who wants to understand how oatmeal affects their morning numbers. The market now reflects this range.
Traditional blood glucose meters remain the most affordable entry point. Walmart's ReliOn brand, CVS Advanced, and the Contour Next series are widely available without a prescription. Test strips are sold over the counter, and many pharmacies offer store-brand options that help keep recurring costs manageable. These meters work well for people who test a few times daily and do not need real-time trend data.
Continuous glucose monitors (CGMs) have become the standard for anyone who needs deeper insight. A small sensor worn on the arm or abdomen measures glucose in the interstitial fluid every few minutes and sends readings to a smartphone. The sensor typically lasts 10 to 15 days before replacement.
The CGM category has split into two paths: prescription devices and over-the-counter options.
Prescription CGMs like the Dexcom G7 and Abbott FreeStyle Libre 3 Plus offer the highest accuracy, with MARD scores (the standard error measurement) around 8% to 9%. These devices integrate with insulin pumps and provide customizable alerts for highs and lows. Medicare covers CGMs for eligible beneficiaries, including those on insulin and certain others who meet the criteria. Private insurance often covers them as well, though prior authorization may be required.
Over-the-counter CGMs arrived as a category in 2024 and have expanded significantly. The Dexcom Stelo, Abbott Lingo, and Abbott Libre Rio are available without a prescription at major retailers and online. The Stelo sensor runs about $49 per unit with a 15-day wear period, putting the monthly cost in an accessible range for many households. These devices are designed for people with Type 2 diabetes not on insulin, as well as those with prediabetes who want to track how food and exercise affect their glucose.
Here is a comparison of the main options available across the U.S.:
| Device | Type | Sensor Life | Rx Required | Best For | Key Limitation |
|---|
| Dexcom G7 | Prescription CGM | 10 days | Yes | Type 1, insulin-dependent Type 2 | Higher cash price without insurance |
| FreeStyle Libre 3 Plus | Prescription CGM | 15 days | Yes | Type 2, budget-conscious users | Fewer alert customization options |
| Dexcom Stelo | OTC CGM | 15 days | No | Type 2 not on insulin, prediabetes | No low-blood-sugar alerts |
| Abbott Lingo | OTC CGM | 14 days | No | Metabolic health tracking | Not for medical decision-making |
| Contour Next EZ | Traditional meter | Per test strip | No | Occasional testing, tight budgets | No trend data, requires fingerstick |
| Walmart ReliOn | Traditional meter | Per test strip | No | Lowest-cost option | Basic features only |
What Real People Are Learning
Maria, a 54-year-old teacher in Dallas, was diagnosed with Type 2 diabetes three years ago. She took her medication, tested fasting glucose each morning, and thought she was doing fine. Her A1c hovered around 7.2%. Then her doctor suggested she try a CGM for two weeks.
"I was shocked," she said. "The same breakfast I had eaten for years—a whole-wheat bagel with peanut butter—was sending my glucose over 200 by 9 a.m. I had no idea because I never tested at that time."
Maria adjusted her breakfast to include more protein and fewer refined carbs. Within three months, her A1c dropped to 6.5%. She now uses a CGM periodically—rather than year-round—to check in on her patterns and make adjustments.
James, a 62-year-old retiree in Florida, was on Medicare and taking multiple daily insulin injections. He struggled with nighttime lows that left him exhausted. His doctor prescribed a Dexcom G7, and the alerts now wake him before his glucose drops dangerously low. "It has been a lifesaver," he said. "I sleep through the night now."
Kevin, a 35-year-old software engineer in Seattle, does not have diabetes. He was curious about the metabolic health trend and bought an OTC Stelo sensor. After two weeks, he learned that his afternoon energy crashes correlated with glucose dips after high-carb lunches. He changed his meal composition and felt more stable throughout the day. Whether this kind of tracking is worth the cost for people without diabetes is a personal decision, but the option exists.
Insurance, Medicare, and the Cost Question
Navigating payment can be frustrating. Here is what to know.
Medicare Part B covers CGM devices for beneficiaries who meet the eligibility criteria, which include having diabetes and using insulin with multiple daily injections or using an insulin pump. The coverage also extends to certain beneficiaries with diabetes who do not use insulin but experience problematic hypoglycemia. You will need a prescription from your doctor and must use a Medicare-approved supplier.
Private insurance coverage varies by plan. Many commercial insurers cover prescription CGMs, but the copay or coinsurance amount differs. It is worth calling the number on the back of your insurance card and asking specifically about durable medical equipment benefits for diabetes monitoring.
For those paying out of pocket, the OTC CGMs have made continuous monitoring far more accessible than it was even two years ago. A monthly supply of Stelo sensors costs under $100, and some people use them for occasional check-ins rather than continuous wear, further reducing the expense.
HSA and FSA accounts can be used to purchase diabetes monitoring supplies, including both traditional meters and CGMs. Keep your receipts.
Patient assistance programs exist through some manufacturers and nonprofit organizations. The American Diabetes Association has a resource page that connects people to financial help based on their state and circumstances.
Practical Steps to Get Started
If you are feeling overwhelmed by the options, here is a reasonable path forward.
Talk to your doctor about a CGM trial. Even a two-week wear can reveal patterns that years of fingerstick testing missed. Many physicians now consider this a standard part of diabetes care. If your doctor is unfamiliar with the newer OTC options, bring information about the Stelo or Libre Rio to the appointment.
Check your insurance coverage before filling a prescription. A CGM that costs one amount through insurance might cost another out of pocket. Sometimes the cash price for an OTC CGM is lower than the insurance copay for a prescription device. Compare before committing.
Learn to read your data. The numbers mean little without context. Most CGM apps now highlight Time in Range, show glucose trends with arrows, and let you log meals and exercise. Pay attention to what happens in the two hours after eating. Notice how a walk after dinner changes the overnight curve. These are the insights that lead to lasting changes.
Find a Diabetes Self-Management Education and Support (DSMES) program near you. Despite its proven effectiveness—studies show it lowers A1c and reduces hospital visits—only a small fraction of newly diagnosed people participate. These programs are covered by most insurance plans and are offered at hospitals, community centers, and increasingly through telehealth. The ADA website has a search tool to locate accredited programs by ZIP code.
Do not rely on a single metric. A1c tells you the average. TIR tells you about stability. How you feel—your energy, your sleep, your mood—tells you about quality of life. All three matter.
The tools available to Americans managing diabetes or prediabetes are better than they have ever been, and the trend toward over-the-counter access means fewer barriers to getting started. Whether you choose a traditional meter, a prescription CGM, or an OTC sensor, the goal is the same: understanding your body well enough to make informed decisions every day.
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