The Dexcom Stelo CGM is the first FDA-cleared over-the-counter continuous glucose monitor in the United States. It is designed for adults 18 and older who are not using insulin — a population that includes many people with type 2 diabetes managed with lifestyle or oral medications, adults with prediabetes, and people simply interested in metabolic health.
What the Dexcom Stelo CGM Is
Stelo is a small, coin-sized biosensor from Dexcom that wears on the back of the upper arm. It measures glucose in the interstitial fluid under the skin, transmits readings via Bluetooth to the Stelo smartphone app, and lasts about 15 days per sensor. Unlike traditional CGMs, Stelo does not require a prescription and is sold directly to consumers.
That over-the-counter status is what makes Stelo unique. It reflects FDA acknowledgment that continuous glucose data is useful for a wider audience than insulin users alone — while still drawing a clear line between wellness-oriented CGM use and medical device use for people who need therapy-level monitoring.
How the Sensor Works
Under the hood, Stelo uses the same type of glucose oxidase chemistry as other modern CGMs. A hair-thin filament generates a small electrical current in proportion to the glucose concentration in interstitial fluid. The device’s algorithm converts that current into an estimated glucose value every few minutes. Sensors are factory-calibrated, so there is no need for fingerstick calibration during normal wear.
Because interstitial glucose lags blood glucose by a few minutes, a sensor reading and a simultaneous fingerstick value can differ slightly, especially during rapid changes. This is physiology, not a defect.
Who Stelo Is Designed For — and Who It Is Not
Stelo’s FDA clearance is specific. It is cleared for adults 18 and older who do not take insulin. Good candidates typically include:
- Adults with type 2 diabetes managed by diet, exercise, and/or oral medications.
- Adults with prediabetes wanting to see how meals, sleep, and activity affect their glucose.
- Generally healthy adults interested in metabolic awareness.
Stelo is not cleared for insulin users, people with type 1 diabetes, or people who have frequent severe hypoglycemia. If you fit any of those profiles, a prescription-grade CGM chosen with a clinician is the more appropriate option.
Accuracy and Specifications
Dexcom reports Stelo accuracy in the single-digit MARD range versus laboratory reference, consistent with current CGM technology. That level of accuracy is sufficient for identifying meaningful patterns — which meals cause spikes, how a walk after dinner blunts post-meal glucose, how overnight numbers respond to late eating — without needing to make insulin-dosing decisions.
| Feature | Dexcom Stelo CGM |
|---|---|
| Regulatory status | First FDA-cleared OTC CGM in the US |
| Intended users | Adults 18+ not using insulin |
| Sensor wear | Approximately 15 days |
| Calibration | Factory-calibrated; no fingerstick calibration |
| Display | Stelo smartphone app |
| Alerts | Not a hypoglycemia management device; alerting is limited compared with prescription CGMs |
| Prescription | Not required |
What the Data Actually Reveals
Most people find the biggest value of Stelo in seeing patterns rather than individual numbers. Common insights include:
- Which breakfasts cause the steepest post-meal spikes.
- How a 15-20 minute walk after dinner compresses the evening glucose curve.
- The effect of short or disrupted sleep on morning glucose.
- How hydration and caffeine interact with meal-time responses.
For many users with prediabetes or non-insulin type 2 diabetes, those insights translate into more effective diet and nutrition choices and help their clinician individualize a broader treatment plan around measured A1C levels.
Limitations You Should Know
- Stelo is not diagnostic. Prediabetes or diabetes diagnosis still requires lab testing.
- Readings lag during rapid glucose changes; short-term spikes can look smaller on the sensor than on a simultaneous fingerstick.
- Compression lows from sleeping on the sensor can produce transient false low readings.
- Stelo does not have the alerting profile of a prescription CGM used to prevent severe hypoglycemia.
- Over-interpretation of day-to-day variability is a common pitfall — patterns matter more than single meals.
How to Use Stelo Responsibly
Used well, Stelo is a powerful nudge toward better habits. Used poorly, it becomes a source of anxiety or over-restriction. A reasonable approach is to wear the sensor for a few weeks at a time, focus on weekly summaries rather than every number, and bring patterns to your clinician rather than changing medications or drastically altering diet on your own.
Medical Disclaimer
This article is educational and does not replace advice from a licensed healthcare provider. Stelo is a wellness-oriented OTC device. Diagnosis, treatment, and any significant change to your health plan should involve your clinician.
The Bottom Line
The Dexcom Stelo CGM opens continuous glucose data to a broader group of US adults for the first time. For non-insulin users with prediabetes, type 2 diabetes, or a strong interest in metabolic health, Stelo can reveal useful patterns without a prescription. It is not a replacement for prescription CGMs in insulin users and not a substitute for medical care. If Stelo is on your shortlist, pair the data with a clinician’s input so insights actually translate into better outcomes.
