Non-invasive Continuous Glucose Monitoring (niCGM) is the holy grail of glucose monitoring. But the quest has been arduous so far; research carried out over the past 35 years has not resulted in in a device with durable availability on the market [1, accessed March 23, 2020].
Two devices have briefly been commercially available. The first, called GlucoWatch Biographer, has been for sale from 2002 to 2007. Poor local tolerability and low accuracy were the limiting factors. The device applied a low voltage current to obtain interstitial fluid transcutaneously. Skin irritation, probably inherent to this technique, together with insufficient accuracy, resulted in withdrawal from the market and dissolvement of the manufacturer .