Continuous Glucose Monitors (CGMs) are an important tool in managing diabetes, providing continuous insights into glucose levels. These compact devices track glucose trends. A common question for many users is whether these devices can withstand water exposure, particularly during activities like swimming.
Water Resistance Capabilities
Continuous Glucose Monitors are designed with varying degrees of water resistance. This resistance is often indicated by an Ingress Protection (IP) rating, where the second digit specifies the level of water protection. For example, an IPX7 rating means a device can be submerged in water up to 1 meter (3 feet) for 30 minutes without damage. An IPX8 rating denotes protection for continuous immersion beyond 1 meter, with specific depth and duration determined by the manufacturer.
Many popular CGM systems offer high water resistance. FreeStyle Libre sensors, including the Libre 2 and Libre 3, carry an IPX7 or IPX8 rating. The Libre 3 has an IPX8 rating, allowing submersion up to 1.2 meters (4 feet) for 30 minutes. Dexcom G6 and G7 sensors and transmitters are also highly water-resistant, capable of being submerged under 2.4 meters (8 feet) of water for up to 24 hours. While the sensors are water-resistant, their accompanying receivers are not and should be kept dry.
Ensuring Adhesion and Protection in Water
Beyond the device’s inherent water resistance, practical steps can enhance a CGM sensor’s adhesion and protection during water activities. Proper skin preparation before sensor insertion is important. Ensure the application site is clean, dry, and free from lotions or oils to create a strong initial bond. Shaving hair from the area can also contribute to better adhesion. Allow any skin prep solutions, such as alcohol wipes, to fully air dry before applying the sensor for optimal adhesion.
For prolonged water exposure or vigorous activities like swimming, additional adhesive support is beneficial. Many users find success with over-patches, which are adhesive coverings placed over the sensor. These patches provide an extra layer of security, helping to prevent the sensor from detaching due to water, sweat, or friction. Medical tapes or specialized protective covers can also reinforce the sensor’s position.
When using these supplementary aids, ensure they are applied smoothly, without wrinkles or air bubbles, to maximize skin contact and create a secure seal. Avoiding direct, strong streams of water hitting the sensor, such as from a high-pressure showerhead, can help preserve its integrity. After swimming, gently patting the sensor and surrounding skin dry, rather than rubbing, can prevent dislodging and reduce the risk of skin irritation.
Monitoring Glucose Readings During and After Water Exposure
While CGM sensors are designed to function in water, consider how water exposure might influence glucose readings. The sensor is located beneath the skin, measuring glucose in the interstitial fluid, so direct water contact does not affect the measurement mechanism. However, extreme temperature changes, such as entering very cold pool water, can temporarily impact interstitial fluid dynamics, potentially causing slight fluctuations or delays in readings.
Some CGM systems may experience temporary signal loss when submerged, as Bluetooth connections do not transmit effectively through water. Real-time readings might not be available until the device is out of the water and the connection is re-established. Modern CGMs, like the Dexcom G7, can store several hours of data even during signal loss, uploading it once the connection resumes.
After water activities, thoroughly dry the sensor site to prevent prolonged moisture under the adhesive patch, which could lead to skin irritation or reduced adhesion. Users should remain aware of their body’s symptoms and compare them with CGM data, especially after water exposure. If concerns arise about reading accuracy or if symptoms do not align with CGM data, verifying glucose levels with a traditional blood glucose meter is an important step for accurate diabetes management.