Dexcom

For one hundred years, diabetics tested blood glucose by pricking fingers. Measuring happened five times daily. Dexcom launched continuous glucose monitors. A sensor under skin measured glucose every five minutes, sending data to smartphones. Cost three hundred dollars monthly. Insurance covered it. Testing changed from snapshots to streams of continuous data. The sensor generated data streams. Doctors saw glucose patterns invisible before. Treatment changed based on continuous data, not snapshots. Patients and physicians built workflows around Dexcom data. Glucose trending, alarm patterns, meal responses, exercise effects became integrated. Switching from Dexcom meant losing this medical history and accumulated data. Once a patient and doctor align treatment around Dexcom data, switching costs increase.