The major CGM brands available in the United States include Dexcom, Abbott’s FreeStyle Libre family, Medtronic Guardian, Senseonics Eversense, and over-the-counter options such as Dexcom Stelo and Abbott Lingo. All of these are FDA-cleared continuous glucose monitors, but they differ meaningfully in wear time, calibration requirements, alerts, accuracy, and who they are designed for.
How CGM Brands Share a Core Design
Every FDA-cleared CGM relies on the same basic principle: a small filament under the skin uses an enzyme to generate an electrical signal proportional to the amount of glucose in interstitial fluid. The device converts that signal into an estimated glucose value and sends readings to a phone, receiver, or linked pump. Differences between CGM brands are mostly about packaging, algorithms, wear time, alert behavior, and insulin pump integration.
Because all CGMs read interstitial fluid rather than blood, there is a built-in physiologic lag of a few minutes, most noticeable during rapid changes. That lag applies across every brand in this article.
Prescription CGM Brands
Dexcom G-Series
Dexcom G6 and the current flagship G7 are widely used in both type 1 and type 2 diabetes, including in insulin users and in some pediatric patients per labeling. Readings update every 1–5 minutes depending on the generation, and the devices integrate with several automated insulin delivery systems. Sensors are factory-calibrated and typically worn for about 10 days. A future Dexcom G8 is expected to continue this trajectory.
Abbott FreeStyle Libre Family
The FreeStyle Libre line ranges from the original scan-based 14 day sensor to FreeStyle Libre 2 (scan + optional real-time alerts) and FreeStyle Libre 3 (fully real-time streaming). Libre sensors are factory-calibrated, applied to the back of the upper arm, and worn for up to 14 days. Libre is particularly popular in adult type 2 diabetes for its balance of accuracy, long wear, and cost.
Medtronic Guardian
Medtronic’s Guardian CGMs integrate tightly with Medtronic insulin pump systems, powering automated insulin delivery in users of the MiniMed pumps. Newer Guardian sensors have moved toward factory calibration. Patients who choose Medtronic’s pump ecosystem often stay within the Guardian family for streamlined closed-loop therapy.
Senseonics Eversense
Eversense is unique among CGM brands. Instead of a replaceable skin-worn sensor, a small fluorescence-based sensor is implanted under the skin of the upper arm by a clinician and lasts several months (with the newer generations extending to around 180–365 days). An external transmitter sits on top of the skin. Eversense appeals to users who prefer a single implantable sensor over repeated self-insertions.
Over-the-Counter CGM Brands
Dexcom Stelo
Dexcom Stelo is the first FDA-cleared over-the-counter CGM in the US, intended for adults 18 and older not using insulin. Sensors last around 15 days, are factory-calibrated, and stream to the Stelo smartphone app. Stelo is designed for awareness, not for insulin dosing.
Abbott Lingo (and Rio)
Abbott’s Lingo platform is the consumer counterpart to FreeStyle Libre, framed around metabolic health and wellness for non-diabetic adults. Additional products aimed at non-insulin-using adults with diabetes have been introduced as the OTC market expanded in the mid-2020s.
CGM Brands Side-by-Side
| Brand / Line | Prescription? | Wear Time | Calibration | Typical User |
|---|---|---|---|---|
| Dexcom G-Series | Yes | ~10 days | Factory | Type 1 or type 2 diabetes, including insulin users |
| FreeStyle Libre 2 / 3 / 14 day | Yes | Up to 14 days | Factory | Type 1 or type 2 diabetes |
| Medtronic Guardian | Yes | ~7 days (varies) | Factory (recent gen) | Users of Medtronic insulin pumps |
| Senseonics Eversense | Yes (implantable) | 180–365 days | Minimal | Adults preferring long-wear implantable sensor |
| Dexcom Stelo | No (OTC) | ~15 days | Factory | Adults 18+ not using insulin |
| Abbott Lingo | No (OTC) | Varies | Factory | Adults 18+ focused on metabolic wellness |
Choosing Between CGM Brands
No single CGM brand is “best” for everyone. The right choice depends on several factors:
- Insulin use: Insulin users generally need a prescription CGM with robust alerts.
- Pump integration: If you use an automated insulin delivery system, sensor compatibility matters.
- Coverage: Insurance or Medicare coverage often narrows the field quickly.
- Wear preferences: Some users prioritize longer wear; others prefer implantables or scan-based devices.
- App and data features: Each brand’s app differs in design, sharing, and report quality.
- Clinician familiarity: Providers often have brands they know best, which simplifies data review.
These decisions should sit inside a broader diabetes or prediabetes strategy — combined with attention to A1C levels, a structured treatment plan, and consistent diet and nutrition habits.
What CGM Brands Do Not Do
No CGM, regardless of brand, diagnoses diabetes on its own — that still requires laboratory testing. CGMs also do not replace clinical judgment. They provide the data that makes informed judgment possible, but interpretation belongs with your care team.
Medical Disclaimer
This article is informational and is not medical advice. Device availability, indications, and features change over time. Confirm current product information from FDA and manufacturer sources, and consult a licensed clinician for brand selection, interpretation of data, and any treatment decisions.
The Bottom Line
The CGM landscape in 2026 is broader than ever, with several prescription brands and a growing set of over-the-counter options. Dexcom, FreeStyle Libre, Medtronic Guardian, and Senseonics Eversense cover most prescription needs, while Dexcom Stelo and Abbott Lingo serve the OTC wellness market. All are accurate enough to be useful, but the right brand for you depends on insulin status, pump ecosystem, coverage, and clinician input. Pick the brand that fits your life and your care plan — not just the one with the loudest marketing.
