I wrote
last month about my diabetes diagnosis this year and my
difficult choice to wear a proprietary device (called a
CGM) on my arm 24/7
to continuously monitor my glucose levels. Like my friend and colleague,
Karen M. Sandler — who previously made a much higher-stakes choice to
receive a proprietary implanted defibrillator to keep her safe given her
genetic heart condition — I reluctantly chose to attach proprietary
hardware and software to my body.
Abbott claims they’re good for 14 days of use but my experience is that they’re worthless after 5 to 10 days. The first 5 days of use they’re about as accurate as the Dexcom units (typically +/- 10%). Beyond that they start to read increasingly low (-50% to -80%) with readings often failing entirely by day 10 or 11. It wouldn’t be a problem if you could replace them after 5 days, but if you do that insurance pitches a fit and refuses to cover more of them because “they’re good for 14 days”.