Biological Therapy

Question 1

Typical Antipsychotics

Answer 1

1) Typical antipsychotic drugs (e.g. chlorpromazine) have been around since the 1950S.
2) They work by acting as antagonists in the dopamine system and aim to reduce the action of dopamine - they are strongly associated with the dopamine hypothesis.

Question 2

Dopamine Antagonists

Answer 2

1) Dopamine antagonists work by blocking dopamine receptors in the synapses in the brain, reducing the action of dopamine.

2) Initially, dopamine levels build up after taking chlorpromazine, but then production is reduced.

3) This normalises neurotransmission in key areas of the brain, which in turn reduces symptoms like hallucinations.

Question 3

Chlorpromazine

Answer 3

1) Can be administered as tablet, a syrup or injection.
2) A maximum dosage of 100mg.
3) Chlorpromazine also has an effect on histamine receptors which can be used as a sedative.
–> It is also used generally to calm anxious patients when they are first admitted to hospital.

Question 4

Atypical Antipsychotics

Answer 4

typical antipsychotic drugs were designed to improve the effectiveness of typical antipsychotics and reduce side-effects.

Question 5

Clozapine

Answer 5

1) Daily dosage ranges from 300mg to 450mg per day.
2) Clozapine binds to dopamine receptors and also acts on serotonin and glutamate receptors, which is thought to improve mood and reduce depression and anxiety.
3) Because of its mood-enhancing properties, Clozapine is often used with patients at high risk of suicide.

Question 6

Risperidone

Answer 6

1) Risperidone is as effective as Clozapine but without the serious side-effects.
2) Maximum of 12mg - Much lower than other antipsychotics.
3) Risperidone binds more strongly to dopamine receptors and is more effective in smaller doses than most antipsychotics and has fewer side effects.

Question 7

Strength of Antipsychotics

Answer 7

EVIDENCE OF EFFECTIVENESS

1) Thornley et al. (2003) reviewed data from 13 trials (1121 participants) and found that chlorpromazine was associated with better functioning and reduced symptom severity compared with placebo.

2) Also support for benefits of atypical antipsychotics. Meltzer (2012) concluded that clozapine is more effective than typical antipsychotics, and that it is effective in 30-50% of treatment-resistant cases.

Question 8

Limitation of Antipsychotics

Answer 8

SIDE EFFECTS

1) Typical antipsychotics are associated with dizziness, agitation, sleepiness, weight gain, etc.
2) Long-term use of typical antipsychotic drugs can result in tardive dyskinesia, which leads to involuntary muscle movements.

–> This means that antipsychotics can do harm as well as good and individuals may avoid them (reducing effectiveness).

(Atypical drugs have reduced side-effects).

Question 9

Limitation of Antipsychotics

Answer 9

DONT KNOW WHY THEY WORK

1) The use of most of these drugs is strongly tied up with the dopamine hypothesis and the idea that there are higher levels of dopamine in the subcortex of SZ.

2) But there is evidence that this may not
be correct and that dopamine levels in other parts of the brain are too
low rather than too high.

–> This means that antipsychotics may not be the best treatment to opt for.