drug therapy

• what are drugs called that reduce symptoms of sz?

  antipsychotics
• how do antipsychotics work?


  by reducing dopaminergic transmission (reducing the action of dopamine in the brain)
• what are the two types of antipsychotics?

  typical antipsychotics

  atypical antipsychotics
• when are typical antipsychotics used?


  used to combat the positive symptoms of sz
• when are atypical antipsychotics used?


  to combat positive symptoms but also it is claimed to impact negative symptoms too
• what are typical antipsychotics?


  the 'first generation' antipsychotics, developed in the 50s

  • basically aim to reduce effects of dopamine + therefore sz
  • they are antagonists
• what is an antagonist?


  the drug binds to the dopamine receptors but does not stimulate it = blocking the effects of dopamine
• what are the effects of typical antipsychotics?


  • hallucinations and delusions diminish in a few days
  • other symptoms may take weeks to go
  • can have side effects where dopamine is blocked in the wrong areas
• what are the conditions for a typical antipsyhotic to be effective?


  Kapur et al, estimates that it must block 72% of D2 receptors in the mesolimbic dopamine pathwayKapur et al, estimates that it must block 72% of D2 receptors in the mesolimbic dopamine pathway

  • however, this means a similar number of D2 receptors must be blocked in other areas of the brain which may lead to side effects
• why are typical antipsychotics high cost?


  • there are several dopamine pathways in the brain
  • blocking the mesolimbic pathway is beneficial for reducing sz
  • blocking others may be harmful for the person
• how are atypical antipsychotics different to typical?


  • a lower risk of side effects
  • have a beneficial effect on negative symptoms
  • suitable for treatment-resistant patients
• how do atypical antipsychotics work?


  blocking D2 receptors remporarily and then dissociate to allow normal dopamine transmission

  • this is thought to lower side effects
• support for antipsychotics


  Leucht et al - meta analysis of 65 studies which involved 6k patients

  • some patients were taken off medication and given placebo and others were given their regular antipsychotic.
  • within 12 months, 64% with placebo relapsed compared to 25% with an antipsychotic
• negatives of the side effects of antipsychotics


  • can cause movement problems for the patient, called extrapyramidal effects (affects the extrapyramidal area of the brain which controls motor activity)
  • the problems can resemble parkinsons disease
  • more than half of patients experience these effects
  • these can be so distressing for the patient, other medication is needed or they stop taking the medication
• advantages of atypical vs typical antipsychotics


  • experience fewer side effects
  • patients are more likely to continue their medication which means they will see a reduction in symptoms
• support for the advantages of atypical antipsychotics


  Crossley et al - meta analysis of 15 studies

  • there were no significant differences between atypical and typical drugs in terms of the effects of symptoms
  • they saw differences in the type of side effects experienced
  • atypical users gained more weight but typicals had more extrapyramidal effects
• negative for drug therapy

  Ross and read argued that when people are prescribed antipsychotic medication, it reinforces that something is 'wrong with them'

  • this prevents the individual from looking at possible traumas or stressors which have led to the condition and therefore reduces their motivation to look for solutions
  • Read suggests that as humans have mostly caused the trauma and disease, it should be human solutions eg cbt that should be used > drugs