Schizophrenia- Biological therapies for schizophrenia: Drug therapy Flashcards
Antipsychotics -
Drugs used to reduce the intensity of symptoms, in particular the positive symptoms, of psychotic conditions like schizophrenia.
Typical antipsychotics -
The first generation of antipsychotic drugs, having been used since the 1950s. They work as dopamine antagonists and include Chlorpromazine.
Atypical antipsychotics -
Drugs for schizophrenia (a psychotic disorder) developed after typical antipsychotics. They typically target a range of neurotransmitters such as dopamine and serotonin.
Examples include Clozapine and Risperidone.
What is the most common treatment for schizophrenia?
The most common treatment for schizophrenia involves the use of antipsychotic drugs.
How can antipsychotics be administered?
Antipsychotics can be taken as tablets, syrup, or injections.
Why are injections of antipsychotics used?
Injections are used for individuals at risk of not taking their medication regularly, as they can be administered every 2-4 weeks.
Are antipsychotics always required long-term?
No, some people may only need a short course of antipsychotics, while others may require them for life to prevent recurrence of symptoms.
What are the two main categories of antipsychotics?
Antipsychotics are divided into typical (traditional) and atypical (second-generation) drugs.
When were typical antipsychotics developed?
Typical antipsychotics have been around since the 1950s.
What is an example of a typical antipsychotic?
Chlorpromazine is an example of a typical antipsychotic.
How is Chlorpromazine administered?
Chlorpromazine can be taken as tablets, syrup, or by injection.
What is the typical dosage range for Chlorpromazine?
The dosage typically ranges from 400 to 800 mg daily, with a maximum of 1000 mg.
How do typical antipsychotics like Chlorpromazine work?
They act as dopamine antagonists, blocking dopamine receptors in the brain and reducing dopamine activity.
What is the dopamine hypothesis in relation to schizophrenia?
The dopamine hypothesis suggests that schizophrenia is associated with higher than usual levels of dopamine activity in the brain.
What additional effect does Chlorpromazine have besides being an antipsychotic?
Chlorpromazine also has sedative properties.
Why is Chlorpromazine used as a sedative?
It is believed to affect histamine receptors, though the exact mechanism leading to sedation is not fully understood.
When are atypical antipsychotics typically used?
Atypical antipsychotics have been used since the 1970s and aim to minimize side effects while maintaining effectiveness.
What is Clozapine and when was it developed?
Clozapine is an atypical antipsychotic developed in the 1960s and first trialed in the early 1970s.
Why was Clozapine withdrawn temporarily?
It was withdrawn in the 1970s due to deaths from a blood condition called agranulocytosis.
Why is Clozapine still used today?
Clozapine is used because it is more effective than typical antipsychotics, particularly in treatment-resistant cases.
What precautions are taken with Clozapine?
Patients taking Clozapine undergo regular blood tests to monitor for agranulocytosis.
How does Clozapine differ from typical antipsychotics in its mechanism?
Clozapine binds to dopamine, serotonin, and glutamate receptors, which may improve mood, reduce depression, and enhance cognitive functioning.
Why is Clozapine sometimes prescribed for high suicide risk?
Its mood-enhancing effects make it suitable for individuals at high risk of suicide.
What is Risperidone and when was it developed?
Risperidone is an atypical antipsychotic developed in the 1990s.
How is Risperidone administered?
It can be taken as tablets, syrup, or an injection lasting around two weeks.
What is the typical daily dose of Risperidone?
The typical daily dose is 4-8 mg, with a maximum of 12 mg.
How does Risperidone compare to Clozapine in binding to receptors?
Risperidone binds more strongly to dopamine receptors than Clozapine, making it effective in smaller doses.
What evidence supports the effectiveness of antipsychotics?
Studies, such as those reviewed by Ben Thornley et al. (2003), show that Chlorpromazine improves overall functioning and reduces symptom severity.
What did Herbert Meltzer (2012) conclude about Clozapine?
Meltzer concluded that Clozapine is more effective than typical antipsychotics and other atypical antipsychotics, particularly in treatment-resistant cases.
What are some side effects of typical antipsychotics?
Side effects include dizziness, agitation, sleepiness, stiff jaw, weight gain, and itchy skin.
What is tardive dyskinesia?
Tardive dyskinesia is a long-term side effect of antipsychotics, causing involuntary facial movements like grimacing and lip smacking.
What is neuroleptic malignant syndrome (NMS)?
NMS is a serious side effect of typical antipsychotics, causing high temperature, delirium, coma, and potentially death.
How have atypical antipsychotics addressed side effects?
Atypical antipsychotics were developed to reduce side effects, though they still exist, such as the risk of agranulocytosis with Clozapine.
What is the relationship between antipsychotics and the dopamine hypothesis?
Antipsychotics are dopamine antagonists, which aligns with the dopamine hypothesis that schizophrenia involves excessive dopamine activity.
What challenges exist regarding the dopamine hypothesis?
Evidence suggests dopamine levels may be too low in some brain areas, raising questions about how antipsychotics, which reduce dopamine activity, can be effective.
What criticisms have been raised about the evidence for antipsychotic effectiveness?
David Healy (2012) suggests some trials have been published multiple times, exaggerating positive effects, and that studies often focus on short-term benefits rather than long-term outcomes.
What is the “chemical cosh” argument?
The argument suggests antipsychotics are used to calm patients for staff convenience rather than for the patients’ benefit, raising ethical concerns.
What ethical issues are associated with using antipsychotics to calm agitated people?
While short-term use is recommended by NICE, some view it as a human rights abuse, questioning the balance between patient care and control.
