Older descriptions often divide CGM into real-time and intermittently scanned or “flash” systems. The ADA 2026 guidance describes this distinction as historical: most currently prescribed personal systems now stream readings without a swipe and provide adjustable alerts. Always compare the exact generation and market version.
Different questions describe different categories
| Distinction | What it describes |
|---|---|
| Streaming versus scan-dependent display | How a particular system makes data available; check current model instructions. |
| Personal versus professional | Who owns/applies the system and the monitoring arrangement. |
| Blinded versus unblinded professional use | Whether the wearer can see readings during the collection period. |
| Prescription versus OTC | A local purchase route with product-specific intended users and limitations. |
Professional CGM
Professional CGM is a clinician-owned/applied system used for a limited monitoring period. It may be blinded or unblinded. Do not assume all professional monitoring hides the readings, or that personal app features are automatically available on a professional configuration.
A U.S. OTC example, with its limits
In its 5 March 2024 clearance announcement, the FDA described Dexcom Stelo for adults 18 and older who do not use insulin. It excluded people with problematic hypoglycemia because the system was not designed to alert them to that condition. This is a dated named-product example, not a complete current OTC directory or eligibility advice for a visitor.
A U.S. OTC clearance does not establish that every CGM can be sold without a prescription or that the same product can be marketed in another country. Check current regulator records and local instructions.
A better comparison checklist
- Readings without scanning, alerts and receiver support.
- Sharing, report export and account requirements.
- Personal or professional workflow, including visibility of results.
- Exact intended users, local access route, recurring supplies and support.
This is general educational information. Use the instructions for the exact device and discuss personal glucose results or treatment questions with your healthcare professional.
Original sources
- American Diabetes Association · Diabetes Technology, Standards of Care 2026
- FDA · first U.S. OTC CGM clearance announcement, March 2024
Sources reviewed 18 October 2026. Model features and local access should be checked against the current instructions and market record.