Antipsychotics Flashcards
Why were atypical antipsychotics developed?
extrapyramidal side-effects associated with the first generation of typical antipsychotics.
Mechanism of action:
- Dopamine D2 receptor antagonists
- blocking dopaminergic transmission in the mesolimbic pathways
Typical antipsychotics
Mechanism of action:
- this generation acts on a variety of receptors (D2, D3, D4, 5-HT)
Atypical antipsychotics
Explain the difference in mechanism of action between typical and atypical antipsychotics
Typical - only antagonise on D2
Atypical - work on many receptors (D2, D3, D4, 5HT)
Common side effects of typical antipsychotics
Extrapyramidal side-effects
hyperprolactinaemia
Typical side effects of atypical antipsychotics
Metabolic effects
Give examples of typical (1st Gen) antipsychotics
Haloperidol
Chlorpromazine
Give examples of atypical antipsychotics
Clozapine
Risperidone
Olanzapine
Give examples of extra-pyramidal side effects
- Parkinsonism
- acute dystonia (sustained muscle contraction)
- akathisia (severe restlessness)
- tardive dyskinesia (late onset of choreoathetoid movements)
Management of acute dystonia
procyclidine
Typical feature of tardive dyskinesia
abnormal involuntary movements e.g. chewing and pouting of jaw
Why has the MHRA issued warnings regarding the use of antipsychotics in the elderly population?
increased risk of stroke/ VTE
Antimuscarinic side effects caused by typical antipsychotics
dry mouth
blurred vision
urinary retention
constipation
What severe side effect of antipsychotics is characterised by pyrexia and muscle stiffness?
neuroleptic malignant syndrome
Antipsychotics are known to sometimes prolong the QT interval. With which agent is this most common?
Haloperidol
