A CGM sensor that peels off early is frustrating, and it can cost you data and money. The good news: most adhesion problems come down to site choice, skin prep and friction, and a few small habits usually help.

Key takeaways

  • Choose a flat, hair-free spot that does not crease when you bend, and rotate sites each time.
  • Clean the skin, let it dry fully, and avoid lotion residue before applying.
  • Press the patch down firmly and smooth out wrinkles after insertion.
  • Overpatches, barrier wipes and adhesive removers can help, but follow your sensor maker's instructions.
  • Irritated, blistered or infected-looking skin is a reason to talk to your care team.

Pick the right spot

Manufacturer guidance, such as Dexcom's, advises avoiding places where skin folds when you bend, areas with a lot of hair, and the zone along your waistband. Scars, stretch marks, moles, lumps and broken skin are also best skipped.

Follow your sensor's approved wear sites (for many sensors this is the back of the upper arm or the abdomen) and rotate each time rather than reusing the same patch of skin. Dexcom also suggests keeping a sensor at least 2.5 cm (1 inch) away from an insulin injection site.

Prepare the skin

Oils, sweat and moisturiser weaken the adhesive bond. A common routine is to wash with soap and water, let the skin dry, wipe with alcohol and let it dry again before applying. Lotion residue is a frequent culprit, so skip moisturiser on that spot beforehand.

If old adhesive is left on the skin from the previous sensor, a medical adhesive remover can clear it so the new patch has a clean surface.

Apply with care

After insertion, press the applicator or patch firmly against the skin and smooth out any wrinkles in the adhesive. Some people add a skin-prep or barrier wipe or an adhesive enhancer under the patch. Keep these away from the spot where the needle goes in, and check your device instructions first.

Overpatches and tape

An overpatch or medical tape can reinforce the edges. Timing can depend on the sensor: Dexcom's guidance differs between its G6 (wait 12 to 24 hours before adding one) and G7 (the included overpatch goes on right away). If your skin is oily or you sweat a lot, an earlier overpatch may help; if your skin is dry, you may prefer to wait and see whether the edges lift.

Sweat, heat and water

Exercise, hot weather, long soaks and clothing friction all wear on adhesive, especially at the edges. If you work out regularly, a well-placed sensor on a low-friction area plus a reinforcing patch may help. Our guide to CGM basics explains what the readings mean, and this post shows how to see workout effects on glucose.

Sensitive or irritated skin

It helps to work out when the irritation happens. If it only shows after removal, a medical adhesive remover and gentler peeling may help. If it appears while you wear the sensor, a barrier product between skin and adhesive may be needed. Some people report less reaction with certain thin-film dressings, but Dexcom notes it has not tested those products with its sensors, so check with your pharmacist or care team first.

Taking the sensor off

Lift an edge and peel slowly, adding adhesive remover if it tugs. Pulling quickly can irritate skin.

When to get help

Redness that spreads, blistering, oozing, pain or signs of infection need medical attention, so contact your doctor or diabetes care team. If a sensor falls off early, contact the manufacturer about a replacement and never reuse a detached sensor.

DiaFitus is not affiliated with Dexcom, Abbott or any sensor maker, and this article is educational, not medical advice.