biological treatment of schizophrenia

• Antipsychotics - the initial treatment for the symptoms of an acute schizophrenic episode ( active psychosis )

  Taken as a pill, syrup or slow release injection

  You may only need this until the acute episode is over, most people take for 1 - 2 years

  They do not cure schizophrenia, but help reduce and control symptoms
• Two types of antipsychotics:

  Typical

  Atypical
• Typical Antipsychotics:

  1950 s

  Chlorpromazine

  An antagonist in the dopamine system ( chemicals reducing the action of a neurotransmitter)

  Works on only positive symptoms

  They block dopamine receptors in the synapse, reduction action of dopamine, normalises neurotransmitter in key areas in the brain, reducing symptoms.

  Has sedative properties by working on histamine receptors too.
• 3 main differences of atypical antipsychotics to typical:

  They have fewer extrapyramidal side effects ( drug induced movements such as shaking or tremors )

  They have a beneficial effect on negative symptoms and cognitive impairment

  They can be used on treatment resistant patients
• Atypical antipsychotics example 1:

  1970 s - aim was to improve effectiveness and minimise side effects

  Clozapine

  Used when all other treatments failed due to severe side effect of agranulocytosis ( life threatening blood disorder )

  Binds to dopamine receptors but also acts on serotonin and glutamate receptors to reduce depression and anxiety
• Atypical antipsychotics example 2:

  1990 s

  Risperidome

  Aim to be effective without previous serious side effects

  Binds to dopamine and serotonin receptors stronger than clozapine, therefore effective in much smaller doses than most antipsychotics

  Evidence suggests this leads to fewer side effects than typically seen with antipsychotics
• Drug treatment timeline :

  1950 s - chlorpromazine typical

  1970 s - clozapine atypical

  1990 s - risperidone atypical
• Chlorpomazine - typical drug made in 1950 s, stops only positive symptoms as is a dopamine antagonist

  Has many extrapyramidal side effects meaning involuntary movement
• Clozapine - atypical drug made in 1970 s aiming to minimise side effects and improve effectiveness. Used as a last resort due to life threatening blood disorder. Reduces anxiety and depression too as binds to not only dopamine receptors but serotonin and glutamate too
• Risperidone - atypical drugs made in 1990 s aiming to be effective without the severe side effects. Stronger than clozapine, effective in smaller doses than most antipsychotics. Binds to dopamine and serotonin receptors
• A limitation to drug therapy for schizophrenia is that there are side effects. Negative side effects such as drowsiness, weight gain, tremors and sexual dysfunction may be worse for patients with schizophrenia than their actual symptoms. These side effects can deter patients from taking their medication at all, and is therefore not always helpful. This decreases the benefit that antipsychotics have to real life. 
• A limitation to drug therapy is that all antipsychotics are dopamine antagonists. Research suggests that schizophrenia can be due to low levels of dopamine in the brain, known in the dopamine hypothesis as hypodopaminergia. However, antipsychotics focus on reducing dopamine because they assume that all schizophrenia is due to hyperdopaminergia, an excess of dopamine. This means that antipsychotics will not always work on everyone.
• Another limitation to drug therapy is that it is very expensive. 10 % of total NHS psychiatric prescriptions is spent on antipsychotics, and more is spent on antipsychotics than any other psychiatric drug, including antidepressants. Also, it is estimated that every year $14.5bn is spent on antipsychotics each year globally. This means that investment into antipsychotics is high and they can be very costly. In countries without universal healthcare, the cost of antipsychotics may make them inaccessible to patients. 
• A strength of atypical antipsychotics is that they may be more beneficial than typical antipsychotics. Atypical antipsychotics don’t usually cause the movement problems found with typical antipsychotics. For example, the chances of tardive dyskinesia are lower. Jeste et al ( 1999 ) found that 30 % of patients on typical antipsychotics suffered from tardive dyskinesia compared to only 5 % taking atypical antipsychotics.