Used primarily to combat +ve
symptoms of condition
Hallucinations + thought disturbances -
supposedly products of an overactive D system
By reducing stimulation of D system
these symptoms can be eliminated
Effectiveness of these drugs in alleviating these
symptoms led to development of D hypothesis
A02
Effectiveness - other factors
are important
Vaughn + Leff
Found antipsychotic medication did
make significant difference bet only for
those living w/ hostility + criticism in their
home environment
In such conditions, R R for those on medication was
53% + those in placebo conditions was 92%
For indivi. living in more supportive home environments, there was no significant
difference between those on medication (12% RR) + those in placebo conditions (15%
RR)
Appropriateness - tardive dyskinesia
CA have many worrying side effects including TD -
uncontrollable movements of lips, tongue, face, hands +
feet
Hill
About 30% of those on this medication
develop this condition + it's irreversible in
75% of cases
Atypical antipsychotics - how they work?
A01
Atypical drugs also act on D system, but are thought to
block serotonin receptors in brain too
Kapur + Remington
Suggest these drugs don't involve serotonin or other
neurotransmitters but only D system + D2 receptors in particular
Help by temporarily occupying D2 receptors + then rapidly
dissociating to allow normal D transmission
This characteristic is thought to be responsible
for lower levels of side effects
A02
Effectiveness - Atypical VS Conventional
Leucht et al
Conducted a meta-analysis of studies published in 1999 + revealed that superiority
of these drugs compared to C ones was only moderate
This analysis found 2 of the new drugs tested were only 'slightly' more effective than C antipsychotics, while other 2 were no more effective
Appropriateness - lower likelihood of TD
Jeste et al
Found TD rates in 30% of people after 9 months of treatment w/ C
drugs but just 5% for those treated w/ atypical drugs
Like conventional antipsychotics they also combat +ve symptoms but there
are claims they have some beneficial effects on -ve symptoms as well
A02
Effectiveness - with negative symptoms
Very marginal support
Leucht et al
Two atypical drugs were 'slightly' more effective than C drugs - one was 'as effective' + one 'slightly worse'
Appropriateness - fewer side effects
Atypical drugs may ultimately be more appropriate for treatment of Sz as there are fewer
side effects which could mean that patients would be more likely to continue their
medications + therefore see more benefits