biological treatments for schizophrenia

Question 1

what are the two types of drug therapy

Answer 1

• typical antipsychotics
• atypical antipschotics

Question 2

what is the AO1 for typical antipsychotics

Answer 2

• E.g. CHLORPROMAZINE. Oldest form of antipsychotic, around since 1950s.
• Daily dosage can go as high as 1000mg, most patients are in the range of 400-800mg.
• Initial dosage is much smaller. This is then built up.
• There is a negative correlation with year and dosage- these days doctors tend to administer much lower dosages. (doctors are prescribing less each year)
• Typical antipsychotics work on the dopamine hypothesis (hyperdopaminergia).
• Chlorpromazine is a dopamine antagonist- it blocks dopamine receptors in the synapses of the brain, reducing the action of dopamine.
• This helps reduce symptoms like hallucinations, and is also an effective SEDATIVE (perhaps by blocking histamine receptors, so works rather like an antihistamine).
• The syrup is absorbed faster than tablets so this is often used upon initial arrival in hospital.

Question 3

what are the AO3 points for typical antipsychotics

Answer 3

• effectiveness (Thornley)
• side effects
• ethics

Question 4

what is the +ve AO3 point for typical antipsychotics

Answer 4

• effectiveness
• Thornley (2003) reviewed studies comparing chlorpromazine to a placebo
• Data from 13 trials with 1121 participants showed chlorpromazine was associated with better overall functioning, reduced symptom severity and lower relapse rate
• Evidence that they are effective + work

Question 5

what are the -ve AO3 points for typical antipsychotics

Answer 5

• side effects
• ethics

Question 6

expand on the -ve AO3 point, side effects (typical)

Answer 6

Typical antipsychotics:
- Dizziness, agitation, sleepiness, stiff jaw, weight gain, itchy skin.
- Involuntary motor action- where prolonged use causes facial spasms like grimacing, blinking, lip-smacking

• NMS (Neuroleptic malignant syndrome)- caused by blockage of dopamine in the hypothalamus and can be fatal. Symptoms range from high temperature, then delirium, to coma. (long term use) (can be fatal)
• This condition has declined over time as doctors are prescribing lower dosages
• (less than 2% of users of anti-psychotics will experience this side effect these days)

Question 7

expand on the -ve AO3 point, ethics (typical)

Answer 7

• Some campaigners claim that practitioners have made inappropriate use of the sedative effects of dopamine
• They claim they have been used in hospitals to calm patients and make them easier to work with rather than to benefit the patients themselves
• NICE guidelines do recommend short-term use with overly agitated patients, however this is a guideline which some campaigners are trying to remove
• We should help them manage their symptoms instead of trying to remove the symptoms
• Are the sedatives to make it easier for the doctors to work with the patients, or for the patients benefit instead of drs

Question 8

what is the AO1 for atypical antipsychotics

Answer 8

• These drugs originated in the 1970s
• The aim was to develop medication as powerful as chlorpromazine but with fewer side-effects, you want the drug treatment to benefit them completely
• e.g. clozapine
• e.g. risperidone

Question 9

what is the AO1 for clozapine

Answer 9

• clozapine is used when other treatments fail.
• Began being used in 1970s.
• People who take it have to have regular blood tests to ensure they are not developing a rare blood condition associated with this type of medication (which killed many patients in the 1970s).
• Because of the potential side effects clozapine is not available as an injection.
• Dosage is lower the chloropromazine, typically 300-450mg a day.
• This drug does not just act on dopamine receptors but serotonin and glutamate receptors too, so it is more powerful, improving mood and depressive symptoms too. Glutamate is also looking to be associated with schizophrenia → +ve
• Between 30 and 50% of patients with schizophrenia attempt suicide so this can be a life-saving medication when patients are suicidal, because of how effectively it improves mood.

Question 10

what is the AO1 for risperidone

Answer 10

• Newer type of atypical antipsychotic (1990s)
• Aim- to be just as effective as clozapine but without the side effects
• Tablets, syrup or injection
• Very small dose – begin at 4-8mg, with a max dosage of 12mg
• Risperidone is believed to be more powerful than clozapine and chlorpromazine
• It binds to receptors more effectively (both dopamine and serotonin receptors)
• This is why only such a small dosage is required

Question 11

what are the AO3 points for atypical antipsychotics

Answer 11

• effectiveness (Meltzer)
• Theoretical Issue - Dopamine Hypothesis

Question 12

expand on the AO3 point, effectiveness (Meltzer) (atypical)

Answer 12

• Meltzer (2012) concluded clozapine is more effective than typical antipsychotics
• Effective in 30%-50% of treatment resistant cases where typical antipsychotics have failed
• However, several studies have compared effectiveness of clozapine and other atypical antipsychotics like risperidone but results have been inconclusive
• perhaps because some patients respond better to one drug than another

Question 13

expand on the -ve AO3 point, Theoretical Issue - Dopamine Hypothesis (atypical)

Answer 13

• there are actually TWO versions of the dopamine hypothesis now.
• Originally it was always thought that hyperdopaminergia was the issue - high levels of dopamine in the subcortex
• Now hypodopaminergia is also highlighted as an issue - low levels of dopamine in the prefrontal cortex.
• If the issue is LOW and not HIGH levels of dopamine, then obviously anti-psychotic medications will not be effective!
• However this does not explain why amphetamines which increase dopamine levels make symptoms WORSE not better.
• Antipsychotic drugs are still by far the most widely used medical treatment.