GlucoWatch G2 Biographer Continuous BG Monitor
Made by Cygnus Inc, Redwood City, California, USA.
This consists of a recorder that looks very much like a large rectangular digital watch and is worn on the wrist in exactly the same way.
The sensor clips into the bottom of the recorder and contains 2 gel discs and an electrode.
When a very low electric current is applied, glucose is drawn through the skin into the gel, where a chemical process takes place. The gel contains an enzyme, glucose oxidase, which reacts with the glucose, forms hydrogen peroxide and this generates an electrical signal that can be converted by the electrode into a measurement of your BG that then shows up on the digital display - in real time.
For the technically minded the process is termed reverse iontophoresis.
AT LAST, no invasive pricking!
Maybe I should have contained my excitement. The sensors only last for 13 hours and each new sensor has to be calibrated by.......you guessed it.......comparing it to a finger stick reading. Oh well, at least some bit is needle free!
It takes 2 hours for each new sensor to 'warm up' after calibration, thereafter it can take readings every 10 minutes. The device is capable of storing up to 8,500 records.
It also contains an alarm. You can set the low and high alert points for your own specific requirements and the alarm will sound when the BG levels exceed those points and also if they are likely to reach the low alert point within the next 20 minutes - which gives you time to eat something to prevent the problem.
The alarm also carries on beeping until you shut it of manually, so offers some small protection against missing it because of being in a noisy environment or asleep.
Unlike the Guardian RT it has been licensed to be used by children from the age of 7 upwards, though supervision by parents is suggested.
This all sounds wonderful but as always this too has it's problems.
1. Though splash resistant i.e. it will not be affected in the rain or if you wash your hands it is not water resistant so you cannot wear it to shower, bath or swim.
2. It will skip readings or turn itself off if there is too much perspiration - and hypoglycaemia is often accompanied by excessive sweating. For those who feel they have only achieved the required level of exercise if they are dripping wet this can also be a problem, as can it's use in a very hot, humid country.
3. The sensors can irritate the skin, causing redness, blisters or intense itching. This may require the use of cortisone creams to control. If you vary the site of placement each time it may help to alleviate this problem.
4. As the sensor attaches with an adhesive pad people who are allergic to medical adhesives (most of you will know if this applies to you because of the rash that occurs when you use a plaster or dressing) you may need to discuss this problem with your doctor before using the GlucoWatch.
5. If you have excess hair on the site where you intend to place the watch - more often a problem in males than females, then you may need to shave that spot.
6. If you are not going to use the sensors within a month you will need to keep them in the fridge, at 2-8deg C (36-46 degF).
7. There is a lag time from the collection of the sample to the displaying of the reading of around 15 minutes. This can be a problem if your levels are dropping swiftly. You will need to remember this when you set the low alert and set it for higher than you need - about 10-20mg/dL higher.
8. Bumping or jolting the watch, which can loosen the adhesive pad, may cause it to give a faulty reading or shut off entirely.
Like the previous systems this is meant to compliment, and nor replace, your regular finger prick meter. It's use is primarily in showing trends, rather than instant BG readings.
To see picture of one, and for more info than I have provided, go to