Back to using Dexcom after 6 months’ sojourn with MedT Guardian 3, and here’s a thing that seems to be a persistent issue for me across both platforms: they both register too low during the dawn phenom hours. Interestingly, they do it differently: the Guardians would track low when the phenom first starts kicking in in the hour or two before I wake up, which was a real problem when I was using the 670 auto mode. The Dexcoms on the other hand are mostly dead-on when I do my a.m. fasting finger stick, but continue to tell me I’m doing great when my BG continues to rise over the next few hours, which means I always have to do a finger stick and, frequently, a calibration around 10:30 to get it back on track by the time of my mid-day meal.
Not sure if the causation is the same for both systems, but it is a PITA, and consistent enough that I really wish I had some kind of fix for it. One thing I’ve noticed about the Dexcom over the 4-5 years I’ve been using them is that they really tend to go a bit whacky when I take my morning shower. Always in the low direction, too, sometimes quite dramatically. FWIW I’ve used various insertion sites, mostly preferring back of the upper arm, but the phenomenon seems to be independent of location. Anyone else experience this, and have you found a reason or a fix? I’ve tried Dexcom support but they just run through all the standard questions and don’t seem to have anything useful to suggest.