Attention deficit hyperactivity disorder (ADHD) is a common childhood
behavioural disorder and medication is one of the principal treatments
. Methylphenidate and dexamphetamine dextroamphetamine) have a long re
cord of use in children and well proven efficacy, and are the preferre
d drugs. Current clinical guidelines recommend a trial of methylphenid
ate and of dexamphetamine for each child meeting criteria for the diso
rder in order to maximise response rate and minimise adverse effects.