biological therapy for sz

Question 1

antipsychotics

Answer 1

drugs used to reduce the intensity of symptoms

Question 2

typical antipsychotics

Answer 2

work as dopamine antagonists and include chlorpromazine

Question 3

atypical antipsychotics

Answer 3

drugs for schizophrenia developed after typical antipsychotics, targeting a range of neurotransmitters such as dopamine

Question 4

what does the term antipsychotic refer to

Answer 4

psychosis, where a person experiences some loss of contact with reality e.g. through hallucinations.

Question 5

How long may antipsychotics be required for

Answer 5

may be required in the short or long term as some people can take a short course without the return of their symptoms but others may require them for life

Question 6

what can antipsychotics be divided into

Answer 6

• typical
• atypical

Question 7

how long have antipsychotics been around for

Answer 7

since 1950

Question 8

example of typical antipsychotic

Answer 8

chlorpromazine

Question 9

how can chlorpromazine be taken

Answer 9

tablets, syrup or by injection

Question 10

what is the maximum oral dose of chlorpromazine

Answer 10

1000mg

Question 11

Liu and de Haan

Answer 11

Typical prescribed does have declined over the last 50 years

Question 12

Dopamine antagonists

Answer 12

block dopamine receptors in the synapses of the brain, reducing their action. According to the dopamine hypothesis, this dopamine-antagonist effect normalises neurotransmission in key areas of the brain, reducing symptoms like hallucinations.

Question 13

sedation effect

Answer 13

Chlorpromazine is also an effective sedative. This is related to its effect on histamine receptors but it is not fully understood how this leads to sedation.

Question 14

other than for psychosis, what can chlopromazine be used for

Answer 14

to calm individuals down, e.g. when they are first admitted to hospital. Syrup is absorbed faster than tablets so this is often used.

Question 15

what is the aim of atypical antipsychotics

Answer 15

maintain or improve on the effectiveness of drugs in suppressing the symptoms of psychosis and reduce the side effects.

Question 16

example of atypical antipsychotic

Answer 16

Clozapine

Question 17

when was Clozapine developed

Answer 17

• was developed in the 60s and 70s
• but withdrawn for a while following deaths of some patients with the blood condition known as agranulocytosis.
• In 80s it was discovered to be more effective than typical antipsychotics,
• so was remarketed as a treatment for when others didn’t work

Question 18

what do people do when on clozapine

Answer 18

take regular blood tests to test for the condition

Question 19

dose of clozapine

Answer 19

It is not available for injection as it has life threatening side effects. Dosage is typically 300-450 mg a day.

Question 20

how does clozapine work

Answer 20

by binding to dopamine receptors in the same way chlorpromazine does

Question 21

what else does clozapine act on

Answer 21

serotonin and glutamate receptors. So this action helps improve mood and reduce depression and anxiety, and may improve cognitive functioning

Question 22

when may clozapine be used

Answer 22

often considered when there is a high risk of suicide. 30-50% of schizophrenics attempt suicide at some point.

Question 23

second example of atypical antipsychotic

Answer 23

Risperidone

Question 24

when was Risperidone developed

Answer 24

90s

Question 25

how can risperidone be taken

Answer 25

in the form of tablets, syrup or injection that lasts for around 2 weeks

Question 26

how does risperidone work

Answer 26

Binds to dopamine and serotonin receptors. It binds more strongly to dopamine receptors than clozapine and is therefore effective in much smaller doses. Some evidence suggests that this leads to fewer side effects.

Question 27

evidence for effecrtiveness - Typical and atypical antipsychotics definitely tackle some symptoms

strength

Answer 27

• Thornley et al reviewed studies comparing chlorpromazine to control conditions
• Data from 13 trials and 1121 ppts showed that the drug was associated with better overall functioning
• Meltzer concluded that clozapine is more effective than typical antipsychotics and it is effective in 30-50% of cases
  Antipsychotics can work

Question 28

counterpoint to evidence for effectiveness

limitation

Answer 28

• Healy identified flaws
• Short term effects and only some successful trials have had their data published multiple times
• Exaggerates size of the evidence base for positive effects
  Less impressive than it seems

Question 29

serious side effects - antipsychotics can do harm

limitation

Answer 29

• Typical antipsychotics have dizziness, agitation, sleepiness, stiff jaw, weight gain and itchy skin
• Long term can result in tardive dyskinesia, involuntary face movements
• Neuroleptic malignant syndrome is the most serious side effect
• Caused when drugs block dopamine action in the hypothalamus
• Results in high temp, delirium, coma, fatal
• Frequency ranges from less than 0.1%-2%

Question 30

mechanism unclear - do not kno whow they work

limitation

Answer 30

• Strongly tied with dopamine hypothesis, which is not a complete explanation as some parts of the brain are low in dopamine
• In this case then antipsychotics should not work
  Some antipsychotics may not be the best treatment