Biological therapies for Schizophrenia: Drug therapy

• Chlorpromazine
  • Strong association between use of TAs and the dopamine hypothesis.
  • TAs work as antagonists in the dopamine system. (Reduce action of neurotransmitter)
  • Dopamine levels build up initially but then production is reduced.
  • Normalises neurotransmitters in key areas of the brain, reducing symptoms such as hallucinations.
  • Effective sedative (histamine receptors).
  • Calm patients with SZ and other conditions.

• Clozapine
  • Withdrawn after deaths due to blood condition (agranulocytosis)
  • Remarketed when discovered to be more effectve than TAs.
  • Regular blood tests.
  • Binds to dopamine receptors.
  • Acts on serotonin and glutamate receptors.
  • Improve mood and reduce depression and anxiety.
  • May improve cognitive functioning.
  • Perscribed when there is high risk of suicide.
• Risperidone
  • More recently developed AA
  • Attempt to produce drug as effective as Clozapine but without side effects

• Thornley et al.
  • Reviewed studies comparing effects of Chlorpromazine to control conditions (placebo) 
  • Chlorpromazine associated with better overall functioning and reduced symptom severity.
  • Relapse rate lower.
• Meltzer
  • Clozapine more effective than TAs and other AAs.
  • Effective in 30-50% of treatment-resistant cases where TAs have failed.
• Results inconclusive for Risperidone.                                                                                             

• Side effects range from mild to serious and even fatal.
• TAs
  • Dizziness
  • Agitation
  • Sleepiness
  • Stiff jaw
  • Weight gain
  • Itchy skin
  • Long term use - tardive dyskinesia (involuntary facial movements)
  • Neuroleptic malignant syndrome
    • High temperature, delirium and coma
    • 0.1-just over 2%

• Idea that high levels of dopamine activity in the subcortex of the brain.
• Evidence to show that this is not a complete explanation.
• Dopamine levels may in fact be too low.
• If this is true then it's not clear how antipsychotics work.
• Modern understanding suggests that they shouldn't work.
• Undermined faith in APs

• Healy
  • Some successful trials have their data published multiple times.
  • Evidence exaggerated of positive effects.
  • Easy to demonstrate positive effects (sedative)
  • Short-term benefits 

The chemical cosh argument

• APs have been used to calm patients in hospitals.
• Benefits staff rather than patients.
• Seen as a human rights abuse.