Schizophrenia: Drug Therapies

Question 1

What are antipsychotics?

Answer 1

• Antipsychotics are a class of medication used to treat many of the symptoms of schizophrenia. Antipsychotics are broadly divided into two groups: the typical antipsychotics and the atypical antipsychotics.

Question 2

How do typical and atypical antipsychotics treat positive symptoms?

Answer 2

• They are both effective at treating positive symptoms of schizophrenia, such as hallucinations and delusions. They treat the symptoms in the same way.
• Their effectiveness results from their action as dopamine antagonists, meaning they block but do not activate dopamine receptors (D2 receptors) without activating them.
• According to the dopamine hypothesis, excessive activity of dopamine neurons in the brains reward pathway causes positive symptoms. By blocking D2 receptors, antipsychotics reduce dopamine activity in the regions, alleviating positive symptoms.

Question 3

What are side effects of extrapyramidal symptoms?

Answer 3

• Extrapyramidal symptoms (eg spasms and motor restlessness)
• They occur because antipsychotics block dopamine receptors not only in areas causing positive symptoms but also in areas of the brains reward pathway causing negative symptoms, disrupting their function.
• Atypical antipsychotics may cause fewer extrapyramidal symptoms, because they temporarily occupy DR receptors and rapidly dissociate (cease binding, freeing up the receptor to bind with dopamine), allowing dopamine to bind. This reduces disruption in brain regions controlling movement compared to antipsychotics.
• Both atypical and typical cause side effects of weight gain and reduced sex drive.
• Clozapine is a widely used atypical antipsychotic, which carries the risk of agranulocytosis (fatal condition)>

Question 4

Atypical antipsychotics treat mood.

Answer 4

• They may improve mood and cognitive deficits in schizophrenia and help treatment-resistant patients.

Question 5

Researcher indicates that both typical and atypical antipsychotics have comparable advantages and
disadvantages for treating schizophrenia.

Answer 5

For example, Crossley (2010) conducted a meta-analysis comparing typical and atypical
antipsychotics, finding both equally effective in reducing positive symptoms. However, atypicals caused
more weight gain, while typicals led to more extrapyramidal symptoms. These findings show that both typical and atypical antipsychotics can be equally useful in treating
some of the symptoms of schizophrenia, demonstrating that all drug therapies can be effective in
treating schizophrenia. However, this evidence shows that both types of antipsychotics cause side
effects. This is a problem as side effects can reduce patient compliance and limit the effectiveness of
these treatments for schizophrenia. Crossley’s findings are particularly persuasive as they come from a
meta-analysis, which combines multiple studies, proucing a large overall sample size. This increases
population validity and allows the results to be generalized to people with schizophrenia

Question 6

There is research support for the interactionist treatment of schizophrenia

Answer 6

Xiong et al. (1994) randomly assigned 63 schizophrenia patients to standard drug care or drug care
plus family therapy. After one year, relapse rates were 61% in the drug-only group and 33% in the
combined treatment group. To some extent this study highlights the limitations of drug therapies, as it shows that combining
medication with family therapy is more effective than relying solely on medication, suggesting drug
therapies by themselves offer a limited treatment for schizophrenia. Nonetheless, these findings don’t
imply drug therapies are ineffective, as many patients (39%) avoided relapse when treated with only
drugs, and they worked even more effectively when used as part of an interactionist approach to
treating schizophrenia. This study’s use of random allocation strengthens its findings, as it means the
differences in relapse rates can be attributed to the use of an interactionist treatment, rather than the
individual differences of the patients allocated to the interactionist treatment condition.

Question 7

A limitation with antipsychotic medications is that they offer a limited treatment for the symptoms
of schizophrenia

Answer 7

A 2015 meta-analysis by Fusar-Poli found that neither typical nor atypical antipsychotics provided
clinically significant benefits for treating negative symptoms of schizophrenia. Given the terrible effect of negative symptoms on the lives of those with schizophrenia, the failure of
antipsychotic medications to treat them means that drug therapies only offer a limited treatment for
schizophrenia. This study’s findings on antipsychotic limitations are highly persuasive, as its meta-analysis
design ensures a large sample size, enhancing external validity, meaning these findings on the limits o drug
therapies can be generalised to the target population of people with schizophrenia.