drug therapy Flashcards
What are the 2 types of drugs used to treat schizophrenia
typical (older) 1960s
Atypical (more modern)
What do typical antipsychotics act as
antagonists to the dopamine system
What is the dopamine system
A collection of nerve cells in the brain
How do the antipsychotics reduce the action of dopamine
blocking dopamine receptors in the synapses
What does the dopamine hypothesis state
the dopamine system of schizophrenia patients is over reactive
Do typical antipsychotic drugs support or deny the dopamine hypothesis
supports
What is chlorpromazine
one of the oldest drugs used in the treatment of schizophrenia
What are the 3 forms of chlorpromazine
- tablet
- syrup
- injection
What is the maximum dosage of chlorpromazine
100mg per day
How is chlorpromazine administered
orally
What happens after taking chlorpromazine
dopamine levels typically rise before falling
What does the dopamine-antagonist effect normalize
neurotransmission in key brain areas reducing symptoms such as hallucinations
What is chlorpromazine useful as
a sedative to calm patients with schizophrenia to deal with their anxiety
What were atypical antipsychotic drugs designed for
improve the effectiveness of typical antipsychotics and reduce side-effects
What’s not known about atypical antipsychotic drugs
How they work
What do Atypical antipsychotic drugs include
Clozapine and Riperidone
When was Clozapine first developed and trialled
1960’s developed
1970’s first trialled
Why was Clozapine withdrawn in the 1970’s
deaths of some patients from agranulocytosis
Why was Clozapine remarketed
success in the treatment of resistant schizophrenia that hadn’t responded to other treatments
What isn’t Clozapine available in the form of and why
injection due to side effects
What is the daily dosage of Clozapine
300-450 mg per day
What does Clozapine bind to
dopamine receptors
Unlike Chlorpromazine what does clozapine act on
serotonin glutamate receptors
What do serotonin glutamate receptors effect
mood and reduces depression and anxiety
What does Clozapine enhance
mood properties
When is Clozapine used on patients
high risk of suicide (phrenics have 40-50% attempted suicide)
What is Riperidone
An antipsychotic drug developed in the 1990’s
Why is Riperidone better to use than clozapine
No serious side effects
How is Riperidone administered
tablet
syrup
injection (2 weeks)
How is the dosage of Riperidone administered
smaller dosages increasing up to 12mg
What does Risperidone bind
dopamine and serotonin receptors
Which drug binds more strongly to dopamine Risperidone or clozapine
Risperidone
Are there any side effects of Risperidone
there are some side effects but these are few
What did Thornley et al (2003) conduct a review of
studies comparing the effects of Chlorpromazine to controls who received a placebo
How many trials and participants did Thornley use
13 trials
1121 participants
What did Thornley’s study conclude
Chlorpromazine was associated with better overall functioning and the reduction of symptom severity
What did Thornley also find in 3 trials of 512 participants in 2003
chlorpromazine reduced instances of relapse
how successful have antipsychotics been
30-50% of treatment resistant cases where other antipsychotics have failed
What did Healy claim evidence of in 2012
the effectiveness of antipsychotic drugs had there successful trials published several times. Exaggerating the claims
Why might some antipsychotic drugs be successful
calming effect and do nothing for the severity of the symptoms
Why have some studies been inconclusive when comparing clozapine with other antipsychotics
some patients respond better to one drug than others
What are the effectiveness of antipsychotics based off of
The premise of dopamine hypothesis which may be an incomplete theory of schizophrenia
What does the dopamine hypothesis say about schizophrenics
The dopamine system is overreactive
What are the side effects of atypical drugs
- dizziness
- agitation
- sleepiness
- stiff jaw
- weight gain
- itchy skin
What can long term use of typical antipsychotic drugs result in
tardive dyskinesia
What does tardive dyskinesia result in
super sensitivity which leads to involuntary muscle movements (grimacing blinking)
What is a neuroleptic malignant syndrome
condition that leads to high temperatures, delirium, coma sometimes death
What percentage of people are affected by antipsychotic drugs
0.1-2%
How has the affection percentage been reduced in taking antipsychotics
Lower dosage levels of new drugs
What have atypical antipsychotics reduced
the frequency of side effects
What do patients who take clozapine take regularly
blood tests to detect agranulocytosis
What’s a significant weakness of antipsychotic drugs
side effects
