biological therapies

• What is the purpose of antipsychotic drugs?

  Intended to reduce psychotic symptoms such as hallucinations, delusions & avolition. (mainly targets positive symptoms). They have been around since the 1950s.
• What are the two types of antipsychotics?

  Typical and atypical
• What is the difference between typical and atypical antipsychotics?

  Atypical antipsychotics are newer and are intended to address many of the issues around typical antipsychotics (side effects etc)
• Typical antipsychotics

  Known as chlorpromazine. Doses are administered orally or by injection starting from 400mg and increasing to a maximum of 1000mg They are dopamine antagonists - block dopamine receptors in synapses of the brain ∴ reducing dopamine action. This prevents dopamine binding to post-synaptic sites and aims to normalise neurotransmission of dopamine in key brain areas. Reduces positive symptoms & has an effect on the histamine receptors∴ calming patients who might be experiencing intense stress or anxiety.

  
• Atypical antipsychotics

  Clozapine- Available as a tablet or a syrup, daily dosage is 300-450mg. Blocks dopamine receptors as well as serotonin and glutamate. Additional targeting of serotonin and glutamate helps reduce negative symptoms and improve mood and cognitive functioning.

  Risperidone- Available in any form- Daily dosage of 4-8mg and a maximum of 12mg. Dopamine and serotonin antagonist- binds strongly to dopaminergic and serotonergic receptors. Binds much more effectively to receptors ∴ a lower dosage is needed and has fewer side effects
• Thornley et al - strength of biological therapies


  Did a double blind study on over 1000 schizophrenia patients. Found that those who received chlorpromazine showed increased functioning, less severe symptoms & lower relapse rates than a placebo group. This demonstrates that effective treatments can be distributed more cheaply and quickly to people who need it than other therapies (e.g. CBT)
• Meltzer (2012) - strength of biological therapies


  Found that clozapine is more effective that typical antipsychotics and that it is effective in 30-50% of treatment resistant cases where other types of antipsychotics have failed ∴ suggesting antipsychotics do work

  Antipsychotics also allow community based care and reduced hospitalisations: Fewer than 3% of people with Sz in the UK are hospitalised.
• Severe side effects - limitations of biological therapies

  Risk of severe side effects. Long term use of chlorpromazine can cause tardive dyskinesia, this is a motor disorder - harms a patients quality of life which in turn crates a risk of symptom substitution.

  Clozapine can cause agranulocytosis. This is a blood disorder cause by a deficiency of white blood cells and is potentially fatal and requires regular blood tests - harms a patients quality of life which in turn crates a risk of symptom substitution.
• Palliative not curative - limitation of biological therapies

  Antipsychotics are a palliative not curative treatment. They only allow patients to manage the symptoms of psychosis rather than target the root cause of schizophrenia. 74% of people discontinue treatment within the first 18 months
• Chemical straightjacket - limitation of biological therapies

  Chlorpromazine has to date of behaviour altering affects which have led some to call it a chemical straight jacket. Has dehumanising affects on patient with schizophrenia by constraining their thoughts and behaviours to make patients easier to manage. Undermines the credibility of antipsychotics as they could be considered a violation of human rights