Schizophrenia - Drug Therapies Flashcards
What are drugs in this area called?
Antipsychotics
What are the 2 types of antipsychotics?
Typical
Atypical
What is an antipsychotic?
Drugs used to reduce the intensity of symptoms, in particular the positive symptoms of psychotic conditons like schizophrenia
What is the typical antipsychotic that you need to know?
Chlorpromazine
What are the atypical antipsychotics that you need to know?
Clozapine and Risperidone
What are typical antipsychotics?
the first generation is an antagonist -
Need to know (eg Chlorpromazine)
What are atypical antipsychotics?
these are the second generation of antipsychotics.
They typically target a range of neurotransmitters such as domaine (because of the dopamine hypothesis) and serotonin (to help treat the secondary symptom of depression)
Need to know (eg Clozapine and Risperidone)
What type of of psychotic is Chlorpromazine?
Typical
Explain Chlorpromazine?
Typical antipsychotic Chlorpromazine
This is taken daily with a dose of up to 1000mg
Typical doses are between 400-800 mg but this has been decreasing recently
There is a strong association between this drug and the dopamine hypothesis as it is an antagonist
Because initially the dopamine builds up in the brain and then production is reduced
Then, according to the dopamine hypothesis the dopamine antagonist effect normalises neurotransmission which may reduce symptoms such as hallucinations
If taken to hospital due to psychosis you will be given this as it is a sedative because it acts on histone receptors. This has a calming effect.
Explain Clozapine?
Clozapine is used when other treatments have failed
Daily dosage is between 300-450 mg per day
It binds to dopamine receptors, similarly to chlorpromazine, however, it also acts on serotonin and glutamate receptors
It may help with our mood and reduces depression and anxiety
When it originality came out it was removed because it increased the chance of a suicidal ideology (between 30-50% attempted suicide) because the increase in serotonin (found in this antipsychotic) can lead to increased anxiety and changes in mood. This can happen within the first 2-4 weeks of taking the medication. The medication is reintroduced in the 1970’s for patients who were a high suicide risk.
Explain Risperidone?
It was developed as an attempt to reduce side effects of clozapine
This drug has smaller doses about 4-8mg up tp 12mg per day
This drug binds ti dopamine and serotonin receptors. However, it has a stronger binding effect on dopamine than clozapine and is effective in lower doses
What is a clear pattern of antipsychotic’s doses?
They get smaller as they get newer
What was the problem with Clozapine when it originally introduced?
When it originality came out it was removed because it increased the chance of a suicidal ideology (between 30-50% attempted suicide) because the increase in serotonin (found in this antipsychotic) can lead to increased anxiety and changes in mood. This can happen within the first 2-4 weeks of taking the medication. The medication is reintroduced in the 1970’s for patients who were a high suicide risk.
What are the positive evaluations of Drug Treatments?
Evidence for its effectiveness
The introduction of Atypical Antipsychotics
What are the negative evaluations for Drug Treatments?
Serious side effects
Dependent on the Original Dopamine Hypothesis
Problems with evidence
The chemicalCosh argument
Explain the positive evaluation for drug treatments: evidence or Effectiveness
• Thornley (2003) reviewed studies comparing the effects of chlorpromazine to control conditions (patients in this condition received a placebo)
• Data from 23 trials with a totalof 1121 patients showed that Chlorpromazine was associated with better overall functioning and reduced symptom severity f’(x)>0
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• Data from 3 trials with 512 patients showed that relapse rates were also lower when the drug was taken
Explain the positive evaluation for drug treatments: Development of Atypical Antipsychotics
Meltzer (2012) concluded that clozapine is more effective that typical antipsychotics and other atypical antipsychotics
He found that it was effective in 30-50% of treatment resistant cases
Meltzer also stated that other atypical antipsychotic drugs have been developed to reduced side effects and have succeeded (good because it will increase the change that patients will take their medicine)
Explain the negative evaluation for drug treatments: Serious Side Effects
Some side effects are mild but they can be fatal
Eg dizziness, agitation, sleepiness, stiff jaw, weight gain and itchy skin
Neuroleptic malignant syndrome - where the drug blocks the dopamine in the hypothalamus
• high temperature, delirium, coma and death
Typical antipsychotics produce - agranulocytosis - a deficiency of granulocytes (a type of white blood cell) causing increased vulnerability to inflection
Explain the negative evaluation for drug treatments: Dependence on the Original Dopamine Hypothesis
The dopamine hypothesis isn’t a complete explanation of Schizophrenia (which didn’t include the hypodomapine hypothesis)
We can therefore suggest that an antagonist can help with schizophrenia symptoms but not a complete solution
Explain the negative evaluation for drug treatments: Problems with Evidence
Healy (2012) has suggested that over publication has lead to misleading positive evidence
Due to the drugs calming effects,it can be concluded that they help patients with schizophrenia
However, most publications discuss short term rather than long term benefits and compare those that have started taking them after withdrawal
Explain the negative evaluation for drug treatments: The Chemical Cosh Argument
NICE recommended using antipsychotics to calm patients
But this could be seen as unethical as you may be risking their life or future
What is Neuroleptic malignant syndrome
Neuroleptic malignant syndrome - where the drug blocks the dopamine in the hypothalamus
• high temperature, delirium, coma and death
What is agranulocytosis?
agranulocytosis - a deficiency of granulocytes (a type of white blood cell) causing increased vulnerability to inflection
