What is continuous glucose monitoring? (CGM)


CGM provides real-time glucose readings throughout the day and night.* Small, wearable CGM devices replace the fingersticks†‡ of traditional blood glucose testing.

On this page, we’ll dive into how CGM works, the benefits it provides, and a bit about the #1 CGM brand worldwide.§

Woman with CGM sensor and reader

1. Sensor is

Most CGM sensors are tiny self-applied devices that sit partially beneath the skin.1 They come with an inserter and have built-in adhesive to help them stick to your skin.1

2. Data is

The sensor measures glucose levels at regular intervals and stores the readings.

3. Scan using a reader or smartphoneǁ

A handheld reader allows you to scan the glucose sensor to collect your information. You may be able to use a smartphone appǁ so that you don't have to carry around an extra device.

Benefits of CGM

Glucose readings without fingersticks†‡

Rather than taking glucose readings from your blood, CGM sensor readings are taken from interstitial fluid, a thin layer of fluid that surrounds the tissue cells below your skin. As carbohydrates are digested, glucose enters your bloodstream before it is absorbed into the interstitial fluid.

See trends and patterns to help better manage diabetes

CGM gives you a view of your glucose levels over time; it can help you keep track of past glucose levels and provide insights into future trends.2

CGM benefits vs. blood glucose monitoring

woman wearing CGM sensor while gardening

FDA-cleared for ages 4 & up

A CGM system FDA-cleared for adults and children with diabetes, ages 4 years and above††3

Real-time glucose alarms#

Now with optional, real-time glucose alarms# that notify you if you go too low or too high

14-day accuracy

Unsurpassed 14-day accuracy4 for adults and children**

Scan and go

Easily check your glucose levels with a painless††3,5 one-second scan instead of a fingerstick

The more affordable CGM system‡‡6

The FreeStyle Libre 2 system is priced 70% below the list price of other CGM systems§§6
Learn more

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Ready to get started with a FREEǁ ǁ trial?

Sign up for the MyFreeStyle program to try one of the FreeStyle Libre systems (CGM) —at no cost.ǁ ǁ
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Woman with CGM sensor

*Based on the sensor being replaced once every 14 days, and scanned at least once every 8 hours.

FreeStyle Libre 2 system: Fingersticks are required if your glucose alarms and readings do not match symptoms or when you see Check Blood Glucose symbol during the first 12 hours.

FreeStyle Libre 14 day system: Fingersticks are required for treatment decisions when you see Check Blood Glucose symbol, when symptoms do not match system readings, when you suspect readings may be inaccurate, or when you experience symptoms that may be due to high or low blood glucose.

§Data based on the number of users worldwide for FreeStyle Libre family of personal CGMs compared to the number of users for other leading personal CGM brands and based on CGM sales dollars compared to other leading personal CGM brands.

IIThe FreeStyle LibreLink app is only compatible with certain mobile devices and operating systems. Please check our compatibility guide for more information about device compatibility before using the app. Use of the FreeStyle LibreLink app requires registration with LibreView.

#Notifications will only be received when alarms are turned on and the sensor is within 20 feet of the reading device.

**FreeStyle Libre 2 system is indicated for use in people with diabetes age 4 and older.

††Data from this study was collected with the outside US version of the FreeStyle Libre 14 day system. FreeStyle Libre 2 has the same features as FreeStyle Libre 14 day system with optional real-time glucose alarms. Therefore the study data is applicable to both products.

‡‡Based on a comparison of list prices of the FreeStyle Libre 2 system versus competitors’ CGM systems. The actual cost to patients may or may not be lower than other CGM systems, depending on the amount covered by insurance, if any.

§§Based on a comparison of list prices of the FreeStyle Libre 2 system versus competitors’ CGM systems, assuming annual use of one receiver (or equivalent hardware) and quantity of transmitters and/or sensors according to use life.

II II or ♢Eligible patients will receive one (1) FreeStyle Libre 14 day sensor or one (1) FreeStyle Libre 2 sensor and reader at $0 copay. The expiration date of the voucher is 60 days from the issue date. This program is not available for patients with gestational diabetes. Only patients 18 and older are eligible to receive an offer for the FreeStyle Libre 14 day sensor, and patients 4 and older are eligible to receive an offer for the FreeStyle Libre 2 sensor and reader. This offer is void where prohibited by law. Abbott may modify or rescind this offer at any time without notice. The discounts are not available to beneficiaries of Medicare, Medicaid or other federal or state healthcare programs or residents of Massachusetts, Puerto Rico and other US territories. The free FreeStyle Libre 14 day sensor or FreeStyle Libre 2 sensor and reader is provided as a sample and is limited to one NDC per eligible person. The FreeStyle Libre 14 day sensor or FreeStyle Libre 2 sensor and reader cannot be re-sold, traded nor submitted to any third party payer for reimbursement and is not provided as any inducement for future purchases. The free sample card is not health insurance.

References: 1. The Endocrine Society. Continuous Glucose Monitoring: Connecting the Dots. Washington, DC: The Endocrine Society, 2020. 2. Reddy, Nihaal, Neha Verma, and Kathleen Dungan. "Monitoring Technologies- Continuous Glucose Monitoring, Mobile Technology, Biomarkers of Glycemic Control". [Updated 2020 Aug 16]. In: Feingold, Kenneth R, et al., editors. Endotext [Internet]. South Dartmouth (MA): MDText.com, Inc.; 2000-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK279046/. 3. Campbell, Fiona M., et al. “Outcomes of Using Flash Glucose Monitoring technology by Children and young people with Type 1 Diabetes in a Single Arm Study.” Pediatr Diabetes 19, no. 7 (November 2018): 1294-1301. https://doi.org/10.1111/pedi.12735. 4. FreeStyle Libre 2 User's Manual. 5. Haak, Thomas, et al. “Flash Glucose-Sensing Technology as a Replacement for Blood Glucose Monitoring for the Management of Insulin-treated Type 2 Diabetes: a Multicentre, Open-label Randomised Controlled Trial.” Diabetes Therapy 8, no. 1 (February 2017): 55-73. https://doi.org/10.1007/s13300-016-0223-6. 6. Data on file. Abbott Diabetes Care.

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Indications and Important Safety Information

FreeStyle Libre 14 day system: The FreeStyle Libre 14 day Flash Glucose Monitoring System is a continuous glucose monitoring (CGM) device indicated for the management of diabetes in persons age 18 and older. It is designed to replace blood glucose testing for diabetes treatment decisions. The System detects trends and tracks patterns aiding in the detection of episodes of hyperglycemia and hypoglycemia, facilitating both acute and long-term therapy adjustments. Interpretation of the System readings should be based on the glucose trends and several sequential readings over time. The System is intended for single patient use and requires a prescription.

CONTRAINDICATIONS: Remove the sensor before MRI, CT scan, X-ray, or diathermy treatment.

WARNINGS/LIMITATIONS: Do not ignore symptoms that may be due to low or high blood glucose, hypoglycemic unawareness, or dehydration. Check sensor glucose readings with a blood glucose meter when Check Blood Glucose symbol appears, when symptoms do not match system readings, or when readings are suspected to be inaccurate. The FreeStyle Libre 14 day system does not have alarms unless the sensor is scanned, and the system contains small parts that may be dangerous if swallowed. The FreeStyle Libre 14 day system is not approved for pregnant women, persons on dialysis, or critically-ill population. Sensor placement is not approved for sites other than the back of the arm and standard precautions for transmission of blood borne pathogens should be taken. The built-in blood glucose meter is not for use on dehydrated, hypotensive, in shock, hyperglycemic-hyperosmolar state, with or without ketosis, neonates, critically-ill patients, or for diagnosis or screening of diabetes. When using FreeStyle LibreLink app, access to a blood glucose monitoring system is required as the app does not provide one. Review all product information before use or contact Abbott Toll Free (855-632-8658) (or visit www.freestylelibre.us) for detailed indications for use and safety information. For full indications for use and safety information, see more here.

FreeStyle Libre 2 system: The FreeStyle Libre 2 Flash Glucose Monitoring System is a continuous glucose monitoring (CGM) device with real time alarms capability indicated for the management of diabetes in persons age 4 and older.*

WARNINGS/LIMITATIONS*: The System must not be used with automated insulin dosing (AID) systems, including closed loop and insulin suspend systems. Remove the sensor before MRI, CT scan, X-ray, or diathermy treatment. Do not take high doses of vitamin C (more than 500 mg per day), as this may falsely raise your Sensor readings. Failure to use the System according to the instructions for use may result in missing a severe low blood glucose or high blood glucose event and/or making a treatment decision that may result in injury. If glucose alarms and readings from the System do not match symptoms or expectations, use a fingerstick blood glucose value to make diabetes treatment decisions. Seek medical attention when appropriate and contact Abbott Toll Free (855-632-8658) or visit * www.freestylelibre.us for detailed indications for use and safety information.

*Please refer to www.freestylelibre.us for the indications and important safety information.

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No use of any Abbott trademark, trade name, or trade dress in this site may be made without prior written authorization of Abbott Laboratories, except to identify the product or services of the company.

This website and the information contained herein is intended for use by residents of the United States.

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