Any driver of any age must notify DVLA of any on-going medical conditions or episodes, at any time not just at licence renewal, that are likely to affect their driving ability. If it is only short term they of course should refrain from driving.
At the age of 70 all drivers have to submit a new application for a continuing driving licence no matter the number of years they have been driving or test passed.
In order to recoup a group B car licence a driver’s application includes a medical questionnaire.
If a minibus licence is required (even driving voluntary) or a medium size goods vehicle 3500 – 7500kg then the application requires a full medical and opticians test rather than the medical questionnaire: thereafter the licence needs to be renewed in the same way every 3 years unless DVLA deems otherwise.
All other licence categories require a full medical and opticians report and subject to yearly renewals thereafter.
It is well documented that the ‘self-regulation’ element of driving licence renewal with the medical questionnaire is widely abused unintentionally or not. Statistics elsewhere give an indication of the abuse. Notwithstanding anything else failure to properly declare medical conditions can invalidate a licence and thereby likewise invalidate insurance cover with immeasurable consequences.