Biological therapies for schizophrenia: drug therapy

Question 1

antipsychotic drugs

Answer 1

• most common treatment for schizophrenia
• can be taken in syrup or tablet form, or injections every 2-4 weeks
• may require short-term or long-term use, with some patients only requiring a short course for the symptoms to stop and not return
• others however may need to take anti-psychotics for the rest of their life
• there are two types of antipsychotics: typical (1st gen.) and atypical (2nd gen.)

Question 2

typical antipsychotics

Answer 2

• typical antipsychotics have been around since the 50s
• Chlorpromazine is a typical antipsychotic
• a strong correlation has been found between the use of chlorpromazine and other typical antipsychotics and the dopamine hypothesis
• these drugs act as antagonists in the dopamine system, meaning that they reduce the action of neurotransmitters
• dopamine antagonists block dopamine receptors in the brain
• initially, dopamine levels build up but production is then reduced
• neurotransmission in key areas of the brain is normalised by these drugs, reducing symptoms such as hallucinations
• Chlorpromazine is not only a treatment for schizophrenia but also an effective treatment, although this is not quite understood

Question 3

atypical antipsychotics

Answer 3

• atypical antipsychotics have been around since the 1970s
• these aim to maintain or improve the effectiveness of typical antipsychotics in suppressing schizophrenic symptoms while also minimising side effects
• Clozapine is an atypical antipsychotic which was developed in the 1960s
• after being withdrawn for a while due to a number of deaths of patients from agranulocytosis, it returned in the 1980s
• it was found to be more effective than typical antipsychotic drugs so re-marketed to be used as a last resort for schizophrenia treatment
• patients on clozapine are given regular blood tests to check for agranulocytosis
• the drug can’t be injected due to its potentially fatal side effects
• this drug binds to dopamine receptors as well as serotonin and glutamate receptors
• this is believed to help improve mood and reduce anxiety and depression for patients
• this means that it is often prescribed if a schizophrenic patient is a high suicide risk
• another atypical antipsychotic is risperidone, which aimed to be as effective as clozapine but without fatal side effects
• this drug binds with dopamine and serotonin receptors, more strongly with the former, which means that it is effective in smaller doses
• there is some evidence to suggest that this leads to fewer side effects than other typical and atypical antipsychotics

Question 4

(+) EVAL - evidence for effectiveness

Answer 4

• there is a large body of evidence to support the idea that both atypical and typical antipsychotic drugs are at least moderately effective in tackling symptoms of schizophrenia
• Thornley et al. (2003) compared effectiveness of chlorpromazine with a placebo in data from 13 tests with 1121 patients
• they found that the drug was associated with better functioning and reductions in symptom severity and relapse rates
• Meltzer found clozapine to be more effective than typical anti-psychotics, working in 30-50% of treatment-resistant cases
• however, studies comparing atypical drugs are inconclusive since some patients are more receptive to one drug over another
• but it does seem that antipsychotic medication is generally reasonably effective

Question 5

(-) EVAL - serious side effects

Answer 5

• side effects of these drugs include: apathy, dizziness, agitation, sleeplessness, stiff jaw, weight gain and depression
• however, if a patient stops taking a drug because of these symptoms, they will start to experience the schizophrenia symptoms, so are stuck in an endless cycle
• in 30% of cases tremors and tardive dyskinesia are present, among other more serious side effects
• the longer the patient takes the drug, the more likely they experience these side effects
• according to Glenmullen (2000), 68% of patients taking these drugs are effected by tardive dyskinesia
• The most serious side effect of these drugs is Neuroleptic Malignant Syndrome (NMS)
• NMS is characterised by a high temperature, comas and even fatality
• however, as doses of antipsychotics reduce so has NMS

Question 6

EVAL - weaknesses of research and antipsychotics

Answer 6

• antipsychotics are based on the dopamine hypothesis, however this is not a complete explanation since in some brain areas the dopamine level is too low for schizophrenics
• it is therefore unclear how antipsychotics work, which undermines faith in this medication
• there is evidence to support effectiveness of this drug therapy but Healy (2012) suggests that much of this evidence has been published multiple times
• he also suggests that the positive effects of the drugs are over exaggerated due to its sedative effects
• most studies focus on short-term effects rather than long-term benefits
• it is widely believed that antipsychotics have been used in hospitals to make patients more malleable and easier to work with, which benefits staff
• NICE recommends their use to calm patients, however, continued use is seen as a human rights abuse by Moncrieff (2013) and others