atypical_antipsychotics_flashcards
What type of antipsychotics should now be used first-line in patients with schizophrenia, according to 2005 NICE guidelines?
Atypical antipsychotics
What is the main advantage of atypical antipsychotics?
A significant reduction in extrapyramidal side-effects
List some adverse effects of atypical antipsychotics.
Weight gain, agranulocytosis (clozapine), hyperprolactinaemia
What serious adverse effect is clozapine associated with?
Agranulocytosis
What is hyperprolactinaemia?
A condition of elevated prolactin levels in the blood
What are some risks of using antipsychotics in elderly patients?
Increased risk of stroke, increased risk of venous thromboembolism
Name an atypical antipsychotic associated with a higher risk of dyslipidemia and obesity.
Olanzapine
Which atypical antipsychotic is known for a generally good side-effect profile, particularly for prolactin elevation?
Aripiprazole
List some examples of atypical antipsychotics.
Clozapine, olanzapine, risperidone, quetiapine, amisulpride, aripiprazole
Summarise atypical antipsychotics
Atypical antipsychotics
Atypical antipsychotics should now be used first-line in patients with schizophrenia, according to 2005 NICE guidelines. The main advantage of the atypical agents is a significant reduction in extrapyramidal side-effects.
Adverse effects of atypical antipsychotics
weight gain
clozapine is associated with agranulocytosis (see below)
hyperprolactinaemia
The Medicines and Healthcare products Regulatory Agency has issued specific warnings when antipsychotics are used in elderly patients:
increased risk of stroke
increased risk of venous thromboembolism
Examples of atypical antipsychotics
clozapine
olanzapine: higher risk of dyslipidemia and obesity
risperidone
quetiapine
amisulpride
aripiprazole: generally good side-effect profile, particularly for prolactin elevation
A 25-year-old man with a history of schizophrenia is prescribed olanzapine. Which one of the following adverse effects is he most likely to experience?
Anorexia
Parkinsonism
Hypertension
Weight gain
Agranulocytosis
Weight gain
Weight gain is an extremely common adverse effect of atypical antipsychotics such as olanzapine
A man calls the local psychiatry crisis team, concerned that his sister - who has previously been diagnosed with schizophrenia - has become more withdrawn and suspicious of her neighbours. He states that she is increasingly worried about them listening to her through the walls. Her symptoms were previously well controlled on daily risperidone. Upon visiting his sister, he found unopened boxes of her medication on the side.
What would be an appropriate future treatment option for this patient?
Change to clozapine
Change to quetiapine
Cognitive behavioural therapy
Consider admission
Depot risperidone injections
Depot risperidone injections
Patients with poor oral compliance to antipsychotics should be considered for once monthly IM antipsychotic depot injections
This patient appears to be having increasing symptoms of psychosis. Giving they were previously well controlled on risperidone, this suggests non-compliance may be an issue. Patients with poor oral compliance to antipsychotics should be considered for once monthly IM antipsychotic depot injections. Their risperidone dose would have to be re-titrated up to their previous dose.
Clozapine can be used for treatment resistant psychosis following trials of two other antipsychotics. From the history, there is no evidence of multiple antipsychotics being trialled and it appears risperidone was controlling the patients symptoms.
If risperidone was not controlling this patients symptoms, another antipsychotic such as quetiapinecould be tried. Following this, if not successful, Clozapine may be trialled providing there are no contraindications.
Cognitive behavioural therapy (CBT) can be helpful in reducing the symptoms of psychosis but is less likely to solve the issue than monthly depot injections.
From the history the patient does not appear to be at risk to themselves or others to warrant admission and attempts should be made to manage them in the community.
Which one of the following side-effects is more common with atypical than conventional anti-psychotics?
Akathisia
Weight gain
Galactorrhoea
Parkinsonism
Tardive dyskinesia
Weight gain
Atypical antipsychotics commonly cause weight gain
The correct answer is Weight gain. Atypical antipsychotics, also known as second-generation antipsychotics, are more associated with weight gain than conventional or first-generation antipsychotics. This side effect is particularly common with medications such as olanzapine and clozapine. The mechanism of weight gain involves the antagonism of serotonin 5-HT2C and histamine H1 receptors, resulting in increased appetite and reduced satiety.
Akathisia is a condition characterised by motor restlessness and a compulsion to move. It’s more commonly associated with the use of first-generation antipsychotics due to their high D2 receptor blockade which can cause extrapyramidal symptoms, including akathisia. While it can occur with atypical antipsychotics, the incidence is lower compared to conventional ones.
Galactorrhoea, or inappropriate lactation, occurs due to elevated prolactin levels. Both atypical and typical antipsychotics can cause hyperprolactinaemia, but this side effect is less common with atypical agents because they have less dopamine D2 receptor blockade in the tuberoinfundibular pathway where prolactin secretion is regulated.
Parkinsonism refers to symptoms that mimic Parkinson’s disease such as bradykinesia, rigidity, tremor and postural instability. These symptoms are more likely to be seen with first-generation antipsychotics due to their strong dopamine D2 receptor antagonism which affects the nigrostriatal pathway involved in motor control.
Lastly, Tardive dyskinesia, characterised by repetitive involuntary movements especially around the mouth area (e.g., grimacing), is another extrapyramidal symptom that’s more frequently observed with conventional rather than atypical antipsychotics. This is because typical agents have a higher affinity for D2 receptors and a longer duration of D2 blockade compared to atypical agents.
