| Alcohol swab concentration | 70% isopropyl alcohol |
| Drying time after alcohol wipe | 30β60 seconds |
| Recommended prep steps | 7 steps |
| Hair removal lead time | 24 hours before application |
| Edge press duration | Minimum 30 seconds |
Key Takeaways
- Clean, dry skin is essential for CGM sensor adhesion
- Proper prep can extend sensor wear time significantly
- Barrier wipes and skin tac products reduce irritation risk
- Hair removal and correct site rotation improve accuracy
Why CGM Skin Prep Matters
Continuous glucose monitors rely on strong skin adhesion to deliver accurate readings. Sweat, oils, lotions, and hair can all compromise sensor contact, leading to early peel-off, inaccurate readings, or skin reactions. A consistent prep routine is the single most effective way to maximise your CGM performance.
Step-by-Step CGM Skin Prep Routine
Step 1: Choose the Right Site
Rotate between approved sites β abdomen, upper arm, or upper buttock depending on your device. Avoid waistbands, scar tissue, and areas with frequent bending. Rotating sites prevents skin breakdown and lipohypertrophy.
Step 2: Remove Hair if Needed
Hair prevents the adhesive patch from lying flat. Use a clean razor or trimmer to shave the area at least 24 hours before application to allow minor skin irritation to settle.
Step 3: Wash with Soap and Water
Wash the site thoroughly with plain soap and warm water. This removes natural skin oils, lotion residue, and dirt. Rinse completely and pat dry with a clean towel.
Step 4: Wipe with an Alcohol Swab
Use a 70% isopropyl alcohol wipe to further degrease the skin. Allow it to dry completely β at least 30 to 60 seconds. Applying a sensor to damp skin is one of the most common causes of early adhesive failure.
Step 5: Apply a Skin Barrier Wipe (Optional but Recommended)
Barrier wipes such as Cavilon or Skin Tac create a protective film over the skin that boosts adhesion and protects sensitive skin from adhesive reactions. Apply in a circular motion and allow to dry fully before sensor placement.
Step 6: Apply the Sensor
Apply your CGM sensor firmly and evenly to the prepped area. Press down on all edges for at least 30 seconds to ensure full contact. Avoid touching the adhesive surface.
Step 7: Secure with an Overpatch
For active lifestyles or humid climates, apply a CGM overpatch or fixation patch over the sensor. These extend wear time and protect against sweat and water exposure. MDS Diabetes stocks a wide range of CGM overpatches and skin prep products compatible with Dexcom, Libre, and Medtronic sensors.
Skin Prep Products Compared
| Product | Purpose | Best For |
|---|---|---|
| Alcohol Swab | Degreasing | All users, every application |
| Skin Tac Wipes | Adhesion booster | Active users, hot climates |
| Cavilon Barrier Wipe | Skin protection | Sensitive or reactive skin |
| IV Prep Wipes | Antiseptic + adhesion | General use |
| CGM Overpatches | Extended wear | Sports, swimming, sweating |
Common Mistakes to Avoid
- Applying to damp or oily skin
- Using moisturiser near the sensor site before application
- Skipping site rotation
- Pressing only the centre β always press the edges firmly
- Using expired or dried-out adhesive products
Sensitive Skin Tips
If you experience redness or itching, try a skin barrier wipe before sensor placement. Patch-test new products 24 hours before use. Hydrocortisone cream applied around (not under) the sensor site can help manage mild reactions. Consult your diabetes care team if reactions persist.