drug therapy

• antipsychotics: 


  used to treat psychotic illnesses such as Sz and bipolar disorder

  recommended as the initial treatment for the symptoms of Sz

  a combination of medication and psychological therapies are used, CBT

  they work by reducing dopaminergic transmission: reducing the action of the neurotransmitter in areas of the brain associated with symptoms of Sz and blocking D2 receptor sites

  thought that Sz produce too much dopamine or have more dopamine receptors than non-Sz

  can't decrease or reduce the number of receptors so we block them using typical antipsychotics
• antipsychotics 


  positive symptoms of Sz are caused by an excess of dopamine in sub-cortical areas especially in the mesolimbic pathway

  negative symptoms are thought to arise from a deficit in dopamine in the mesocortical pathways

  typical: (1950's) chlorpromazine, used to combat positive symptoms

  atypical: (1970's) clozapine used to combat positive and negative
• how the drugs work

  typical: dopamine antagonists

  block D2 receptors sites at the synapse in the brain reducing the action of dopamine, normalises dopamine levels and reduced hallucinations

  chlorpromazine has a sedation effect and reduces anxiety

  atypical: to improve the effectiveness of typical drugs

  reduce some of the side effects of typical drugs, target dopamine, serotonin and glutamate receptor sites, improves mood and cognitive function

  risperidone is a newer antipsychotic drug but works in small doses
• side effects

  typical-

  mild: dizziness, sleepiness, agitation, dry mouth

  moderate: lip-smacking, grimacing, constipation

  severe: tardive dyskinesia (uncontrollable muscle movement in face), tremor, fever and altered mental capacity

  atypical- more manageable and not as long lasting

  mild: dizziness, sleepiness, dry mouth

  moderate: weight gain, grimacing, constipation, cardiovascular issues
• typical: 1950's to reduce the effects of dopamine

  typical antipsychotics are dopamine antagonists as they bind to dopamine receptors and block their actions

  effectiveness of dopamine antagonists led to the development of the dopamine hypothesis

  kapur et al (2000) estimate that between 60% and 75% of dopamine receptors in the mesolimbic pathway need to be blocked to be effective

  however this results in side effects
• atypical: 


  second generation: 3 main differences

  low risk of extrapyramidal side effects

  beneficial effect on negative symptoms and cognitive impairment

  suitable for treatment-resistant patients

  also act by blocking dopamine receptors but only temporarily

  then rapidly dissociate to allow normal dopamine transmission

  they do have the same effects on movement as typical drugs
• evaluation: antipsychotics compared to placebo

  studies have compared relapse rates of both drugs

  Leutch et al (2012) carried out a meta-analysis of 65 studies involving 6000 patients all p's had been stabilised on either typical or atypical antipsychotics, some p's were then take off antipsychotics and given a placebo instead, within 12 months 64% of placebo patients relapsed compared to 27%
• evaluation: extrapyramidal side effects 


  typical drugs can produce movement problems for the patient, they effect the extrapyramidal area of the brain that helps control motor activity

  most common: parkinsonian symptoms which resemble the features of Parkinson's disease

  the symptoms can be so severe patients may stop taking the drug
• evaluation: ethical problems 


  critics argue that is the side effects, death and psychological consequences were taken into account a cost-benefit analysis would be negative

  in the US, a large court settlement was given to tardive dyskinesia sufferer on the basis of violating the human rights acts -'no one shall be subjected to inhuman or degraded treatment

  which drugs are better:

  atypical: gained more weight

  typical: experienced more extrapyramidal side effects

  concluded no differences in efficacy, just side effects
• issues and debates 


  economic implications: patients get back into work and deal symptoms but the productivity and experience of patients is important

  reductionism vs holism:

  drug therapy follow the lowest level of explanation (biological) when we should be diagnosing and treating using the holistic experience simplest explanation good for targeted treatment, not as good as it misses other factors of Sz

  nature vs nurture: drug therapy vs psychological treatments (CBT)

  interactional approach is needed for treatment, drugs +CBT works better than drugs alone