Drug Therapy

Question 1

What can antipsychotics be divided into?

Answer 1

• typical (traditional) and atypical (second generation drugs)

Question 2

When have typical drugs been around since?

Answer 2

1950s

Question 3

What is a common typical antipsychotic?

Answer 3

• chloropromazine

Question 4

What has happened to typical prescribed dosages over the last 50 years?

Answer 4

• they have declined

Question 5

Typical - What is there a strong association between the use of typical antipsychotics and?

Answer 5

• the dopamine hypothesis

Question 6

Typical - How do typical antipsychotics work?

Answer 6

• by acting as antagonists in the dopamine system

Question 7

Typical - What are antagonists?

Answer 7

• chemicals which reduce the action of a neurotransmitter

Question 8

Typical - How do dopamine antagonists work?

Answer 8

• by blocking dopamine receptors in the synapses of the brain, reducing the action of dopamine

Question 9

Typical - What happens when a person initially starts taking typical antipsychotics?

Answer 9

• dopamine levels build up but then its production is reduced

Question 10

Typical - According to the dopamine hypothesis how do dopamine-antagonists work?

Answer 10

• the dopamine-antagonist effect normalises neurotransmission in key areas of the brain, reducing symptoms like hallucinations.

Question 11

Typical - What is the sedation effect?

Answer 11

• as well as having antipsychotic properties, chlorpromazine is also an effective sedative

Question 12

Typical - How can chloropromazine be used to have a sedation effect?

Answer 12

• it is often used to calm individuals not only with schizophrenia but with other conditions too, often when patients are first admitted to hospitals and are very anxious

Question 13

Atypical - When have atypical antipsychotics been used since?

Answer 13

• the 1970s

Question 14

Atypical - What is a common atypical antipsychotic and when was it used?

Answer 14

• Clozapine as a treatment to be used if other treatments fail

Question 15

Atypical - What is a negative of atypical antipsychotics?

Answer 15

• they have potentially fatal side effects, so patients taking them have to have regular blood tests and it is not available as an injection.

Question 16

Atypical - How does clozapine work?

Answer 16

• by binding to dopamine receptors in addition to acting on serotonin and glutamate receptors.

Question 17

Atypical - What effect does clozapine have on the body?

Answer 17

• helps to improve mood and reduce depression and anxiety in patients and may improve cognitive functioning.

Question 18

Atypical - When are atypical antipsychotics usually administered?

Answer 18

• when an individual is considered at high risk of suicide, which is important because about 30-50% of people with schizophrenia attempt suicide at some point.

Question 19

Atypical - What is risperidone?

Answer 19

• it was developed to produce a drug as effective as clozapine but without its serious side effects.

Question 20

Atypical - Why is risperidone more effective than clozapine?

Answer 20

• it binds more strongly to dopamine receptors and there is some evidence to suggest that this leads to fewer side effects than antipsychotics

Question 21

Evaluation - Evidence For Effectiveness

Answer 21

• Strength = support for the effectiveness of antipsychotics
• Large amount of evidence to support the idea that both typical and atypical antipsychotics are at least moderately effective in tackling the symptoms of schizophrenia.
• Thornley et al: Reviewed studied comparing the effects of chloropromazine to control conditions. Data from 13 trials with a total of 1121 particpants showed that chloropromazine was associated with better overall functioning and reduced symptom severity compared to a placebo.

Question 22

Evaluation - Effectiveness of Clozapine

Answer 22

• Review by Meltzer concluded that clozapine is more effective than typical antipsychotics and other typical antipsychotics and that it is effective in 30-50% of treatment-resistant cases where antipsychotics have failed.

Question 23

Evaluation - Counterpoint For Effectiveness

Answer 23

• Healey: suggested serious flaws with evidence for effectiveness.
• For example, most studies are of short-term effects only and some successful trials have had their data published several times, exaggerating the size of the evidence base for positive effects.
• Also, because antipsychotics have powerful calming effects, it is easy to demonstrate that they have some positive effect on people experiencing symptoms of schizophrenia. This is not the same as saying that they reduce the severity of psychosis.

Question 24

Evaluation - Serious Side Effects

Answer 24

• Limitation = likelihood of side effects
• Typical antipsychotics side effects: dizziness, agitation, sleepiness, stiff jaw, weight gain and itchy skin.
• Long term use can result in tardive dyskinesia which is caused by dopamine sensitivity and causes involuntary facial movements such as blinking and lip-smacking.
• The most serious side effect is neuroleptic malignant syndrome (NMS) which is believed to be caused when the drug blocks dopamine action in the hypothalamus.
• NMS results in high temperature, delirium and coma and can be fatal.