UPDATE: NONINVASIVE GLUCOSE MONITORING

Arriving in the 1960s, the home blood glucose monitor was a tremendous advance over urinalysis. Reasonably instantaneous glucose measurement was now possible, and "tight control" could now take place. But improvements since then have been incremental; you still need to draw a drop of blood. However minor, blood glucose testing still requires the need to prick yourself with a sharp object.

For thirty years, people have dreamed of a noninvasive glucose monitor, some device that would read blood sugar levels without self-inflicted pain. It hasn't happened yet.

Recognizing there are millions of dollars spent every year on blood glucose monitoring, a number of companies have tried to develop a monitor that would produce a reliable reading without the need to bleed. A number of different techniques have been tried, and there have been many failures. Some have produced litigation. Meanwhile, we bleed, drop by drop.

The demand for a "stick-free" glucose monitoring device will continue until it is fulfilled. Different companies will continue trying, and eventually one will succeed. When the U.S. Food and Drug Administration (FDA) is satisfied that a new monitor works as promised, and that its results are within accepted standards for reliability, it will be approved, and we will see it on the market. Until then, there will be updates like this one. So what's on the immediate horizon?

The most promising new development appears to be the Glucowatch, produced by Cygnus, Inc., of Redwood City, California. The Glucowatch system uses a sensor on the wrist (the Glucowatch), and a replaceable sensing "patch" (the Autosensor). Cygnus anticipates filing for FDA approval later this year.

Bioject Medical, of Portland, Oregon (not to be confused with Biocontrol, whose early machine was rejected by the FDA), in partnership with Elan Corporation, has developed a similar "watch" type machine, but one that uses different chemical and mechanical principles. They have not yet filed for FDA approval.

While the above machines would be worn on the body, and would provide more-or-less continuous readings, another set of monitors utilize infrared, or near-infrared, spectroscopy, to read and measure blood glucose. Biocontrol and Futrex (the Dream Beam), two early competitors, employed this technology, as does a prototype from CME Telemetrix, of Waterloo, Ontario, Canada.

There are many more. While these companies and their competitors sort out issues of accuracy, reliability, and cost, several others are pursuing new uses for pre-existing technology. These are the "semi-invasive" glucose monitors, worn like an insulin pump, providing continuous readings. Insulin pump manufacturer MiniMed, of Sylmar, California, filed for FDA approval of such a semi-invasive device in December of 1997. Several other companies are working on similar machines at this time.

The future will bring things we have not imagined: self-adjusting insulin pumps, noninvasive meters with continuous readout and hypoglycemia alarms... It won't be long now.