What is FreeStyle Libre 3? Uses, warnings & side effects

Download the FreeStyle Libre 3 app to a smartphone.

• Open the app and set up the alarms in the app.

• Disable the phone’s automatic operating system updates.

• Always keep the smartphone’s Bluetooth turned on.

• Do not force close the app on the phone.

• Keep the phone charged.

Any headphones or speakers should be detached from the phone if they’re not being used.

Keep the phone within thirty-three (33) feet of the sensor at all times.

The sensor can also be used with the FreeStyle Libre 3 reader. 

How to place a sensor:

• Read the Sensor Application Guide and Adhesion Guide before placing the sensor on the skin.

• Sensors that are damaged or have passed their expiration date should not be used.

• Always place the sensor on the flat part of the back of the arm.

• Wash the application site with non-moisturizing, fragrance-free soap and then wipe the skin with an alcohol swab.

• Completely dry the skin.

• FreeStyle Libre 3 sensors are attached with an applicator.

• Remove the sensor applicator cap. Set it aside.

• Line up the mark on the applicator with the mark on the sensor pack.

• Press the applicator firmly against the skin on the back of the arm.

• Make sure the sensor is firmly attached.

• Place the cap back on the applicator.

• Ask the pharmacist how to properly dispose of the applicator.

After a sensor is in place:

• Decide if you want to use the smartphone app or reader. You can only connect the sensor to one or the other.

• Scan the sensor with either the smartphone app or reader. The User Guide has instructions for each.

• Take a reading on the smartphone app or reader to check the sensor.

• You can check glucose readings 60 minutes after the sensor has been scanned into the app or reader.

• Check the accuracy of the sensor’s readings for the next 12 hours by taking regular blood sugar fingerstick tests.

• The operating range of the sensor is between 50°F and 114°F.

• The sensor can be immersed in water up to three feet deep for up to 30 minutes. 

Keeping a sensor in place:

• You can use a bandage, medical-grade tape, Tegaderm I.V., Torbot Skin-Tac, Mastisol Liquid Adhesive, or Skin-Prep Protective Barrier Wipes to help keep the sensor in place. Follow the instructions that come with these products.

• Don’t play with the sensor.

• Be careful not to dislodge the sensor. Try not to hit or brush objects with the sensor arm. Wear loose-fitting clothing. Be careful when putting on and taking off clothes over the sensor. 

• After showering, bathing, or swimming, pat the area dry. Do not rub it with a towel or washcloth.

• Exercise or heavy sweating can loosen the sensor.

How to replace a sensor:

• Freestyle Libre 3 sensors must be replaced after 14 days.

• FreeStyle Libre 3 Plus sensors must be replaced after 15 days.

• Replace a sensor when the app indicates it needs replacing, if it’s coming loose, or if you see the tip. Do not try to re-apply a sensor that is coming loose.

• Do not reuse sensors.

• To remove a sensor, pull up the adhesive edge.

• Carefully peel it off the skin.

• Be careful when removing and throwing away the sensor. The sensor can spread infections. 

• Choose a different location to attach the new sensor. 

• Ask the pharmacist how to dispose of the sensor. Disposal laws vary by location.

How to store unused sensors:

• Store unused FreeStyle Libre 3 sensors at room temperature between 39°F and 82°F. 

• The sensors may not work properly if they are exposed to temperatures outside this range.

• If the temperature gets too hot, store the sensors in the refrigerator.

• Protect unused sensors from extreme humidity (higher than 90%).

How to use FreeStyle Libre 3 Plus sensors with an insulin pump:

• The FreeStyle Libre 3 Plus system works with the Beta Bionics iLet Bionic Pancreas automated insulin delivery pump. It is not compatible with any other insulin pump.

• Install the current iLet app on your smartphone. Make sure it is paired with the iLet insulin pump and that the pump’s firmware is updated.

• In the iLet app, click “Switch CGM Sensor” on the CGM menu and change the CGM sensor type to “Abbott Libre 3 Plus.”

• In the iLet app, start a new sensor. Click “Start Sensor” on the Settings/CGM screen and scan the new sensor.

If you have forgotten to replace a sensor, do it when remembered. 

Use another method to measure glucose levels until you’ve replaced the sensor.

FreeStyle Libre 3 sensors should not be used by:

• Critically ill patients

• People on dialysis

FreeStyle Libre 3 sensors must be removed before any MRI scan, CT scan, or any high-frequency electrical heat treatment (diathermy). The scan or treatment may damage the sensor.

When a sensor is removed for a medical procedure, always replace it with a new sensor.

Before using FreeStyle Libre 3, make sure the prescriber knows if you:

Are pregnant

On dialysis

Have any other implanted medical device

Tell all doctors and other healthcare providers treating you that you are wearing a FreeStyle Libre 3 sensor.

The FreeStyle Libre 3 sensor will not provide accurate tissue glucose readings in people who are:

• Dehydrated

• Have low blood pressure

• In shock

• With extremely high blood sugar levels (hyperglycemic-hyperosmolar state)

FreeStyle Libre 3 sensor readings are not always accurate. You must perform a fingerstick blood test to get an accurate blood sugar reading in any of the following situations:

• The smartphone app or reader displays a Check Blood Glucose symbol

• The sensor reading has no number

• You experience symptoms of high or low blood sugar

• Sensor readings don’t match the way you feel

• You suspect the readings aren’t correct

You must check blood sugar levels in the first 12 hours after a sensor is attached.

Drink plenty of fluids to stay hydrated. Dehydration and water loss can give inaccurate readings. 

Do not share the app with any other person.

The sensor can cause allergic reactions. If you notice skin reactions or irritation beneath or around the sensor, remove the sensor and contact the doctor.

Some medications, supplements, and personal care products can affect the sensor’s accuracy, particularly:

• High-dose vitamin C (> 500 mg) 

• Aspirin

• Some skin care products

Tell all doctors and other healthcare providers treating you that you are wearing a continuous glucose monitoring system before they prescribe any new medications.