drug therapy

• antipsychotics

  • used to treat schizophrenia
  • all work by reducing dopaminergic transmission - reducing action of dopamine in areas associated with symptoms (based on dopamine hypothesis)
• types of antipsychotics

  • typical used to combat positive symptoms - products of overactive dopamine system (eg. chlorpromazine)
  • atypical combats positive and negative symptoms (eg. clozapine)
• typical antipsychotics

  • dopamine antagonists (bind to and block dopamine receptors)
  • d levels build up, then production reduced
  • reduce stimulation of dopamine system in mesolimbic pathway = reduction in positive symptoms
  • many side effects
• atypical antipsychotics

  • dopamine antagonists (bind to and block dopamine receptors)
  • temporarily occupy receptors, rapidly dissociation
  • fewer extrapyramidal side effects
  • claimed to have effect on negative symptoms too
• evidence for antipsychotics over placebos

  Leucht et al meta-analysis

  • some taken off antipsychotic medication, given placebo
  • within 12 months
  • placebo 64% relapsed, antipsychotics only 27% relapsed

  so, value as prevents relapse, use should still be weighed against side effects
• ethical issues due to side effects

  extrapyramidal side effects

  • movement problems such as tardive dyskinesia (involuntary movements)
  • may be v distressing for patient - may stop taking
  • lawsuits seeking compensation for suffering caused by tardive dyskinesia more common
• atypical may be better than typical

  Crossley et al meta-analysis

  • no significant diffs in effect on symptoms (efficacy)
  • BUT atypical had less extrapyramidal side effects - eg. less severe tardive dyskinesia

  patients more likely to continue with medication = more likely to see symptom reduction
• motivational deficits

  Ross and Reid

  • argue when people given antipsychotics, reinforces idea than something is wrong with them
  • prevents them from thinking about other possible contributing stressors
  • reduces motivation to find solutions to stressors