AN alarm the size of a wrist watch is being developed for people with diabetes to warn them whenever their blood sugar level is too high or too low.

Researchers at Cranfield Biotechnology Centre, Bedfordshire, are developing a chemical biosensor that can be injected underneath the patient's skin. The sensor is connected to a wrist-watch-sized monitor and triggers an alarm whenever the wearer's blood sugar level is outside the norm.

It is estimated that the sensor, which should become available within the next few years, will cost under pounds 5, says a report in Doctor.