Antipsychotics

Question 1

What are examples of first generation/typical antipsychotics?

Answer 1

Chlorpromazine, Haloperidol, Sulpride, Flupentixol, Trifluoperazine, Fluphenazine, Zuclopenthixol

Question 2

What is the mechanism of action of first gen/typical antipsychotics?

Answer 2

These are strong antagonists of Dopamine D2 receptors in cortical and striatal areas. The amount they bind to D2 receptors correlates with clinical potency. They are all dopamine D2 blockers, but each agent has distinct effects on other neuronal receptors e.g. 5HT2A, Alpha1, histamine, muscarinic, which correspond to variable side effect profiles.

Question 3

What are the antidopaminergic side effects? (also EPSEs)

Answer 3

• Acute dystonia
• Akathisia
• Parkinsonism
• Tardive dyskinesia

Question 4

What are the antiadrenergic side effects?

Answer 4

postural hypotension

sexual dysfunction

Question 5

What are the anticholinergic side effects?

Answer 5

• dry mouth
• reduced swelling
• urinary retention
• constipation
• blurred vision
• precipitation of glaucoma

Question 6

What other side effects do first generation/typical antipsychotics have?

Answer 6

• cardiac arrhythmias
• weight gain
• amenorrhoea
• galactorrhoea
• hypothermia
• neuroleptic malignant syndrome

Question 7

What are examples of second generation/atypical antipsychotics?

Answer 7

Olanzapine, Clozapine, Risperidone, Quetiapine, Amisulpride, Aripiprazole

Question 8

What is the mechanism of action for second generation antipsychotics?

Answer 8

All Dopamine D2 blockers but with lower binding affinity. So, this means that they selectively antagonise mesolimbic D2 receptors more than those in the nigrostriatum and prefrontal cortex. Also block 5HT2a receptors

Question 9

Why are EPSEs less likely to be caused by second gen/atypical antipsychotics?

Answer 9

the Extra-Pyramidal Side Effects (EPSEs) that are caused by nigrostriatal blockade occur less frequently as well as the effects due to mesocortical blockade e.g. neurocognitive impairment and negative symptoms.

Question 10

What are side effects to look out for with atypical antipsychotics?

Answer 10

weight gain
diabetes
agranulocytosis -clozapine (present with sore throat and white dots on tongue)

Question 11

Which EPSEs may still occur withs second gen/atypical?

Answer 11

• Cardiac problems
• Anticholinergic problems
• Sedation
• Hypotension