Zusammenfassung der Ressource
Biological therapies for Schizophrenia
- Conventional antipsychotics - how they work?
- A01
- Their basic mechanism is to reduce levels of dopamine + thus reduce symptoms of Sz
- They are dopamine antagonists
- They bind to D receptors (particularly D2
receptors) but don't stimulate them
- Blocking their action
- A02
- Effectiveness - relapse rates
- Davis et al
- Found significant difference in terms of R R between
treatment + placebo group in each study reviewed
- Demonstrating therapeutic effectiveness of drugs
- Analysed results of 29 studies
- Found relapse occurred in 55% of patients in placebo group
+ 19% who remained on antipsychotic
- Ross + Read
- Point out these figures are
misleading
- Indicate 45% of those on placebo did benefit
- Appropriateness - motivational deficits
- Ross + Read
- Argue being prescribed medication reinforces view
that there is 'something wrong with you'
- Prevents indivi. from thinking about possible stressors
that might be a trigger for their condition
- Reduces motivation to look for poss solutions that might alleviate
their stressors + reduce their suffering
- Conventional antipsychotics - target positive symptoms
- A01
- 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
- Atypical antipsychotics - positive + negative symptoms
- A01
- 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