Drug Therapy Flashcards
Define “typical antipsychotics”
Are dopamine antagonists in that they bind to but do not stimulate dopamine receptors and so reduce the symptoms of schizophrenia.
Define the term “atypical antipsychotics”
Carry a low risk of extrapyramidal side effects, have a beneficial effect on negative symptoms and cognitive impairment, and are suitable for treatment-resistant patients.
What are the use of antipsychotics?
- To reduce dopamine in areas of the brain associated with symptoms of schizophrenia.
Give an example of a typical antipsychotic
Chlorpromazine
Give an example of an atypical antipsychotic
Clozapine
Outline the benefits of typical antipsychotics
- Reduce dopamine by binding to but not stimulating dopamine receptors in the mesolithic pathway.
- Eliminate hallucinations and delusions
Outline the costs of typical antipsychotics
- Kapur et al (2000) - between 60% and 75% of d2 receptors in the mesolimbic pathway must be blocked for these drugs to be effective = in order to do this must block other areas of the brain = undesirable side effects
Outline the benefits of atypical antipsychotics
- Carry a lower risk of extrapyramidal side effects
- Have a beneficial effect on negative symptoms
- Suitable for treatment-resistant patients.
- Have a stronger affinity for serotonin receptors and a lower affinity for dopamine receptors.
What is also a difference between typical and atypical antipsychotics?
- Atypical = act on dopamine system by blocking d2 receptors but only temporarily then rapidly dissociate to allow normal dopamine transmission
Why is rapid dissociation a benefit of atypical antipsychotics?
- Leads to lower extrapyramidal side effects - have little effect on the dopamine system that control movement.
AO3
Is there a difference between antipsychotics and placebos?
P: Research support = antipsychotics > placebos.
E: Leucht et al (2012) - meta-analysis of 65 studies, involving nearly 6,000 patients.
Some given placebo, while others remained on medication.
Within 12 months = 64% of placebo patients relapsed compared to 27% of antipsychotics
E: Clearly shows superiority of antipsychotic drugs compared to placebo in preventing relapse
A03
What are the side effects that typical antipsychotics can produce?
P: Can produce movement problems = extrapyramidal side effects - as drugs impact extrapyramidal area of brain, which helps control motor activity.
E: More than half of patients = symptoms of Parkinson’s Disease.
When taken for a long time = tar dive dyskinesia, i.e involuntary movements of the tongue, face and jaw.
E: Side effects = distressing to patient leading to other drugs to control them or they may stop medication completely
AO3
Are typical antipsychotics subject to ethical problems?
P: Problems with typical drugs raise ethical concerns
E: Recently in the US, a large out of court settlement was awarded to a tardive dyskinesia sufferer on the basis of Article 3 of the Human Rights Act, which states that ‘ no one shall be subjected to inhuman or degrading treatment or punishment’
E: Suggests that is side effects, deaths and psychosocial consequences were taken into account, a cost-benefit analysis of typical antipsychotics would most likely be negative.
AO3
What are the advantages of atypical over typical antipsychotics?
P: Atypical = more advantages. Key advantage = fewer side effects
E: Atypical - newly developed drugs like olanzapine and quetiapine, are less likely to produce extrapyramidal side effects commonly found in typical drugs.
E: Patients more likely to continue with medication = reduction in symptoms.
AO3
Is there a difference between atypical and typical drugs in terms of reduction of symptoms or side effects?
P: The info of atypical drugs = more superior than typical. may not be the case.
E: Crosley et al (2010) - meta-analysis of 15 studies to examine efficacy (reduction of symptoms) and side effects.
Found = no difference in terms of effect on symptoms
Found = difference in side effects. Typical = more extrapyramidal side effects. Atypical = gained more weight.
E: Concluded no differences in efficacy between the two, but clear difference in side-effect profile.