Drug Therapy for Schizophrenia (AQA A Level Psychology)

Typical antipsychotics

• Antipsychotic drugs are used to treat a range of mental disorders, including schizophrenia (psychotic refers to any condition in which a person loses touch with reality)

• Typical antipsychotics are also known as first generation antipsychotics as they have been in use since the 1950s

• Typical antipsychotics are dopamine antagonists i.e. they inhibit dopamine activity by blocking dopamine receptors in the synapse

• Examples of typical antipsychotics include chlorpromazine, trifluoperazine, acetophenazine and haloperidol 

• Typical antipsychotics are effective at treating the positive symptoms of schizophrenia e.g. delusions

• Haloperidol and chlorpromazine come with side effects, some of which are quite severe e.g. drowsiness, agitation, dry mouth, blurred vision, lack of emotional response, dizziness, muscle stiffness or spasms

• Over-use of typical antipsychotics may lead to tardive dyskinesia (sensitivity to dopamine) or neuroleptic malignant syndrome (a result of dopamine being blocked in the thalamus) which can be life threatening

Typical antipsychotics are dopamine antagonists as they block dopamine receptors in the brain.

Atypical antipsychotics

• Atypical antipsychotics are second generation antipsychotics developed in the 1980s as a solution to the potentially damaging side effects of typical antipsychotics

• Atypical antipsychotics are dopamine antagonists i.e. they inhibit dopamine activity by blocking dopamine receptors in the synapse but they may act as serotonin agonists i.e. they inhibit serotonin reuptake in the synapse

• Atypical antipsychotics treat both the positive and negative symptoms of schizophrenia

• Examples of atypical antipsychotics include risperidone, olanzapine, brexpiprazole, and clozapine

• Clozapine is prescribed when other antipsychotic drugs have not worked: it also helps to reduce tardive dyskinesia

• Clozapine may act on serotonin receptors which can help to balance mood 

• Risperidone is thought  to act in the same way as antidepressants 

Research which investigates drug therapies

• Marder & Meibach (1994) - Schizophrenic patients who took risperidone compared to haloperidol or a placebo showed significant improvement in both positive and negative symptoms 

• Geddes et al. (2000) conducted a review of research and found that there is no real difference in terms of effectiveness between first and second generation antipsychotics: typical antipsychotics should be prescribed in the early stages of an episode of schizophrenia unless the patient has previously had side-effects which included disjointed movement including muscles spasms

Evaluation of drug therapies

Strengths

• There is a body of compelling research evidence which suggests that antipsychotics are an effective treatment for schizophrenia

• Antipsychotics are most effective at treating patients with the most severe symptoms who may not be treatable using non-drug therapies (Furakawa et al. 2015)

Weaknesses

• Patients with milder, less extreme forms of schizophrenia benefit less from taking antipsychotics and may additionally experience adverse side-effects  

• It is not clear as to how effective antipsychotics are in preventing relapses in patients who are in remission

Link to Issues & Debates:

Any form of drug therapy used to treat a complex, multi-layered disorder such as schizophrenia is bound to suffer from biological reductionism as the idea that a tablet/syrup/injection can treat that disorder does not consider the whole person and the range of factors which may contribute to and exacerbate their condition.