The law requires HGV & PSV drivers to be in reasonably good health in order to legally operate commercial vehicles on public roads. To that end, every new driver must undergo an HGV/PSV medical exam with accompanying paperwork (D4) that is submitted to the DVLA by the physician who performs the examination.
Medical examination report for a lorry or bus driving licence (D4) A doctor will need to complete this form if you are applying for a lorry or bus driving licence.
Existing drivers are required by the DVLA to have a medical at the age of 45 and then every five years until the age of 65. After 65, the medical must be done every year.