Medtronic Guardian Sensor Adhesion — Preventing Early Fall-Off

Hello. The Medtronic Guardian 4 and Guardian 3 sensors are worn for up to 7 days. If your sensors are falling off before the week is up, here is how to improve adhesion without compromising the sensor or transmitter. Step 1: Choose the right insertion site. Guardian sensors are approved for the abdomen and the back of the upper arm, depending on your pump and software version. The abdomen provides good adhesion for most users. The upper arm experiences more movement and sweat, making adhesion more challenging. If arm sensors consistently fall off, try switching to the abdomen. Step 2: Prepare the skin thoroughly. Wash and dry the site. Wipe with an alcohol swab and wait at least 60 seconds for the alcohol to fully evaporate before inserting the sensor. Skin that is not fully dry will reject adhesive. Step 3: Use skin prep wipes before insertion. IV Prep wipes by Smith & Nephew are specifically designed for medical adhesive applications. They both clean the skin and add a light adhesive layer. Apply one wipe, let the skin dry to a slight tackiness, then insert the sensor. Step 4: Apply an overpatch immediately after insertion. Do not wait until the sensor starts to lift. Medtronic offers sensor overtapes, and third-party options like Simpatch for Medtronic Guardian or GrifGrips CGM patches are cut specifically to fit around the Guardian transmitter without covering it. Apply on the first day. Step 5: Protect the transmitter-sensor connection. The Guardian transmitter sits elevated above the sensor base. When applying an overpatch, leave the transmitter base uncovered — the patch should border the transmitter, not cover it. Covering the transmitter can trap moisture and affect signal. Step 6: Use waterproof tape for swimming or heavy exercise. Tegaderm transparent film dressings can be cut into a frame around the sensor for additional protection during high-sweat activities. Replace the tape after water exposure and let the site dry before reapplying. Step 7: Rotate your site. Guardian sensors inserted repeatedly in the same location will develop scar tissue, which reduces both adhesion and sensor accuracy. Map out at least 6 to 8 rotation sites and cycle through them, allowing each site 4 to 6 weeks of rest before returning. Step 8: If the sensor fell off before 7 days — contact Medtronic. Call 1-800-646-4633. Medtronic typically provides replacement sensors for premature adhesion failures. Have your sensor lot number and the date of insertion ready. Still need help? Find a CGM provider near you →