Essential hypertension is quite rare in childhood or adolescence. A secondary cause behind the raised blood pressure should therefore be searched, e.g. renal disease, aortic coarcation, endocrine causes, raised intracranial pressure etc. Blood pressure medication should not be commenced before aetiological examinations have been conducted in specialist care. Further examinations conducted by a specialist are needed if the blood pressure values measured in a child exceed the 95th percentile values repeatedly (table ).