pav your link was pasted incorrectly, it should be:
http://www.bedfordshirediabetes.org.uk/downloads/Updates 2014/Driving_leaflet-v3[1].pdf
It's covered in this sites sponsor's page:
https://www.diabetes.org.uk/Guide-to-diabetes/Life-with-diabetes/Driving/
You should only have to tell the DVLA if your medical team (GP) tells you that you should. Mandatory notification is if you are put on insulin. It is wise however to tell your insurer. The above apply to normal car drivers, if you drive a bus, lorry etc then different rules apply.
The definitive answer is of course on the DVLA pages and their leaflet is here:
https://www.gov.uk/government/uploa...ed-by-non-insulin-medication-diet-or-both.pdf
If you do have at any time to fill in the DVLA DIAB1 form then take great care over your answers.
Good luck with the Gliclizide.