Like "I ran super low for months, only 3 or 4 highs in that time frame. Now, after the new medicines tossed in for Addison's and Insulin, I'm running sky high. My only way of knowing is my eyes. They burn, hurt, blurr, high or low. I don't think I've ever had a false negative that I know of. When I was running 20 to 30, I was cold, but sweating, speach was slurred and could barely walk. Still with me, low or high, I do get a warning and it's my eyes. Hope it gets better for you, Angie "