Mental Health Nursing

222 Acute Mental Health Nursing
In practice, because of their classical affinity for dopamine D 2 receptors,
risperidone and ziprasidone will, at high doses, induce EPS. The same is
not true of clozapine, olanzapine and quetiapine, however, which have a
much weaker affinity for D 2 receptors and as a result do not have the
propensity to induce EPS at higher doses (Bigliani et al., 1998). It has
been proposed, but not confirmed, that risperidone and ziprasidone have
a low incidence of EPS because of serotonin–dopamine interactions in the
basal ganglia. Serotonin blockade appears to reverse the effects of dopamine
D 2 blockade, but only in the nigrostriatal system and not in the mesolimbic
system (Kapur and Remington, 1996). Clozapine, olanzapine and quetiapine
in contrast appear to have a naturally high affinity for dopamine
receptors in the mesolimbic system (Bigliani et al., 1998) and consequently
a low propensity to induce EPS.
There is convincing evidence for the efficacy of conventional antipsychotics.
However, they may tend to be used in higher than necessary
doses and are generally poorly tolerated. There are few data to assist in the
management of many of these symptoms and the treatment of acute EPS is
challenging. Novel and atypical anti-psychotics are generally very well tolerated
and have a low propensity to induce many of the problematic sideeffects
associated with conventional treatments (Gray, 1999). Guidelines
have been published to guide clinicians on how to effectively use antipsychotics
and minimise side-effects (Taylor et al., 2001), although concern
has been repeatedly expressed that clinicians fail to follow such guidance.
To summarize so far:
• schizophrenia is a serious mental disorder;
• anti-psychotic medication is effective at treating predominantly the
positive symptoms of the illness;
• typical anti-psychotics suffer from serious side-effects including EPS
that need careful treatment and management;
• atypical anti-psychotics are much better tolerated and do not cause EPS.
The problem of non-compliance
There is good evidence that in schizophrenia, the prophylactic use of antipsychotic
medication reduces the risk of relapse (Kane, 1989; Marder,
1999). However, a number of studies have demonstrated that compliance
with anti-psychotic medication is generally poor and not taking medication
is associated with a substantial increase in relapse rates, more frequent
hospitalisations and a generally poorer outcome in people with
psychotic illnesses (Gabel and Piezcker, 1985; Helgason, 1990). Kemp
et al. (1997) have proposed that the so-called ‘revolving door phenomenon’