Syncope is the medical term for loss of consciousness, or blackouts.
There are many potential causes for this. In common is the transient lack of adequate blood supply to the brain, which is typically made worse by being in the upright position.
Usually, the description of the episode and the symptoms associated with it are the most important aspect to determine the cause.
It is important to make sure that the heart is structurally normal (that there is no heart valve narrowing and that the pumping function is good) and that there is no evidence of wear and tear of the electrics of the heart (which may predispose to periods of a very slow heart beat) which could be treated with a pacemaker.
Expert opinion should be sought if the cause of blackouts remains unclear. If there is concern that blackouts may be due to a heart rhythm disturbance, then an implantable loop recorder (ILR) may be recommended.
In addition, the individual should report to the DVLA in case a driving restriction applies.