wasn't there a product called glucowatch about 10 years ago? Allegedly it read your BG through the contact with the skin. Stock shot up in the dot com glory days. Here is an old article about it. Obviously it was a bust or it would be all the rage
Up until now, all home blood glucose testing has relied on extracting a drop of blood from the body. The GlucoWatch monitor uses a process called reverse iontophoresis, which causes interstitial fluid to migrate across the skin's surface. This is the clear fluid just underneath the surface of the skin that surrounds cells. You might see interstitial fluid ooze from a scrape on the skin surface. Both interstitial fluid and blood contain glucose. The GlucoWatch monitor also uses an electro-chemical sensor to obtain glucose readings every 20 minutes.
One of the advantages of this method is that drugs do not interfere with measured glucose levels, which is why Echo (ECTE) is going after the critical care market. The DXCM technology (seven) is going after the home market.
The two compliment each other well, which is why I have positions in both companies.