There is much less information on how much stimulant medication
is diverted into illicit use. In particular, there is no published
data from Europe on this matter. It is therefore important that
clinicians (including GPs who write many of the prescriptions)
continue to monitor the use of these drugs carefully to ensure that
patients, their peers, their families or those dispensing the
medication at school or in residential care settings do not abuse
them. Care must also be taken when assessing adolescents prior to
starting treatment with stimulant medications. A careful drug
history is mandatory and these drugs should be used with discretion
and utmost caution where there is a previous history of drug
misuse.
From the pharmacological point of view, it is worth noting the
elegant work carried out by Volkow and colleagues which is
summarised in Swanson and Volkow
(2001). These studies demonstrated that whilst intravenous
methylphenidate resulted in a "high" similar to that experienced
with cocaine, oral methylphenidate was not associated with the same
drug-induced euphoria. The reason for this is the much slower onset
of dopamine transporter blockade in the striatum that results from
oral doses of methylphenidate.