A03- Biological Therapies

• Evidence for effectiveness (Chlorpromazine)

  Thornley et al reviewed studies comparing the effects of chlorpromazine to conttrol group where people with schiz receieved a placebo. Data from 1121 ppts showed chlorpromazine was associated with better overall functioning, decreased severity of symptoms and relapse rates.
• Evidence for effectiveness (Clozapine)

  Meltzer concluded that clozapine is more effective than typical anti-psychotics and other anti-psychotics in 30-50% of treatment-resistant cases. But individual differences important to note as one drug may work for one person and another drug may not, so findings are inconclusive,
• Serious side effects

  Typical anti-psychs are associated with dizziness, agitation, sleepiness, weight gain, etc... Long term use can lead to tardive dyskinesia which is caused by dopamine hypersensitivity and causing involuntary face movements.
• Serious side effects (NMS)

  Neuroleptic malignant syndrome is the most fatal and is caused by drugs blocking dopamine action in the hypothalamus. Only 0.1-2% achieve this though. Although atypical anti-psychs produce less side effects, blood tests still have to be taken.
• Use of antipsychotics depends on the dopamine hypothesis


  More theoretical issue than a practical one but evidence shows how original dopamine hypothesis is not a complete explanation for schiz and dopamine levels in parts of the brain other than the subcortex are too low rather than too high.
• Use of antipsychotics depends on the dopamine hypothesis (Casuality)

  It is not clear how antypical anti-psychs are able to help with schiz when they reduce dopamine levels. Modern understanding suggests anti-psychs should not work.
• Problems with the evidence of effectiveness

  Healy suggests some studies that had their data published multiple times exaggerated the evidence for positive effects. Due to their powerful calming effect, it is easy to show that they are positive effects on people with schiz. But this is not the same as actually decreasing severity of psychosis.
• Problems with the evidence of effectiveness (Lack of valdidity regarding short and long term)

  Most studies assess short-term benefits rather than long term benefiits and so it is unknown what these long term effects are.
• The chemical cosh argument


  Although short term use of anti-psychs to calm agitated people is recommended by the National Institute for Health and Clinical Excellence (NICE), this practice can be seen as abusing human rights.