Biological Treatment - Drug Therapy

Question 1

What does it involve?

Answer 1

• Use of antipsychotic drugs in the short (people take a short course and then stop without return of symptoms) or long term (require them for life or face likelihood of a recurrence of schizophrenia)

Question 2

Dopamine Antagonists

Answer 2

• Typical antipsychotics like chlorpromazine work by acting as antagonists (chemicals which reduce neurotransmitter action) in the dopamine system
• Dopamine antagonists work by blocking receptors at the postsynaptic neuron, reducing action of dopamine – with chlorpromazine, dopamine levels build up and then lower
• According to the dopamine hypothesis, this dopamine-antagonist effect normalises neurotransmission in key areas of the brain, reducing symptoms like hallucinations

Question 3

Sedation Effect

Answer 3

• Chlorpromazine is also an effective sedative – believed to be related to its effect on histamine receptors
• Chlorpromazine is often used to calm individuals with schizophrenia and other conditions

Question 4

Atypical Antipsychotics

Answer 4

• Aim was to maintain/improve upon the effectiveness of drugs in suppressing the symptoms of psychosis, and also minimise the side effects

Question 5

Clozapine

Answer 5

• Binds to dopamine receptors in the same way that chlorpromazine does, but it also acts on serotonin and glutamate receptors – this may help improve mood, reduce depression and anxiety, and may improve cognitive functioning
• Mood-enhancing effects mean that it’s sometimes prescribed when an individual is considered at high risk of suicide – 30-50% of schizophrenics attempt suicide at some point
• Had fatal side effects of agranulocytosis (blood condition) - patients take blood tests to prevent it; also means it can’t be an injection

Question 6

Risperidone

Answer 6

• Risperidone is believed to also bind to dopamine and serotonin receptors – it binds more strongly to dopamine receptors than clozapine and is effective in much smaller doses than most antipsychotics
• There is some evidence to suggest that this leads to fewer side effects than other antipsychotics

Question 7

Evaluation - Evidence to support effectiveness

Answer 7

• Thornley et al (2003) reviewed studies comparing effects of chlorpromazine to control conditions, with data from 13 trials with a total of 1121 participants showing that chlorpromazine was associated with better overall functioning and reduce symptom severity as compared to placebo
• Meltzer (2012) concluded that clozapine is more effective than typical antipsychotics and other atypical ones, and that it is effective in 30-50% of treatment-resistant cases where typical antipsychotics have failed

Question 8

Evaluation - Evidence is base isn’t as impressive

Answer 8

• Healy (2002) suggested serious flaws with evidence for effectiveness, describing how most studies are of short-term effects, some successful trials have had data published multiple times (exaggerating size of evidence base), and it’s easy to demonstrate that antipsychotics have some positive effect on people experiencing symptoms given their powerful calming effects (it’s also different from saying they reduce severity)

Question 9

Evaluation - Likelihood of side effects

Answer 9

• Typical antipsychotics are associated with a range of side effects (dizziness, agitation, sleepiness, stiff jaw, weight gain, itchy skin)
• Long term use can result in tardive dyskinesia, which is caused by dopamine supersensitivity and causes involuntary facial movements like grimacing, blinking, and lip-smacking)
• Most serious side effect is neuroleptic malignant syndrome (NMS), which is believed to be caused when drug blocks dopamine action in hypothalamus, and results in high temperature, delirium, and coma

Question 10

Evaluation - Antipsychotics may be a ‘chemical cosh’

Answer 10

• Antipsychotics may have been used in hospital situations to calm patients and make them easier for staff to worm with, rather than to benefit the patients themselves
• Short-term use of antipsychotics to calm patients is recommended by NICE, however the practice is seen by some as a human rights’ abuse – this raises ethical issues in the use of antipsychotics drugs with schizophrenia patients

Question 11

Evaluation - Theoretical objection to the use of antipsychotics

Answer 11

• Their usage is strongly tied to the dopamine hypothesis and the idea that there are higher than usual levels of dopamine in the brain’s sub-cortex, but there is evidence that suggests this may not be correct and that dopamine levels in other parts of the brain are too low rather than too high, meaning that antipsychotics shouldn’t work
• This had undermined faith of some people that any positive effects are actually due to the pharmacological effects of antipsychotics