Antipsychotics

Question 1

What are the possible indications for antipsychotics?

Answer 1

Schizophrenia

Schizoaffective disorder

Bipolar disorder

Psychotic depression

Augmenting agent in treatment resistant anxiety

Question 2

What are the characteristics of typical antipsychotics?

Answer 2

D2 dopamine receptor antagonists

Extrapyramidal side effects common

Can be split into low potency and high affinity

Low potency: Interact with nondopaminergic receptors, causing cardiotoxic and anticholinergic side effects

High potency: Higher risk of extrapyramidal side effects due to high affinity for D2 receptors

Question 3

What are some examples of low and high potency typical antipsychotics?

Answer 3

Low potency- chlorpromazine, thioridazine

High potency- fluphenazine, haloperidol, pimozide

Question 4

What are the characteristics of atypical antipsychotics?

Answer 4

Serotonin-dopamine 2 antagonists

Don’t get extrapyramidal side effects but do cause weight gain

Question 5

What are some examples of atypical antipsychotics?

Answer 5

Risperidone

Olanzapine

Quetiapine

Aripiprazole

Clozapine

Question 6

What treatments can be given in antipsychotic resistant patients?

Answer 6

Clozapine

If clozapine fails:

• Add another antipsychotic
• Add lithium/anticonvulsant
• ECT

Question 7

What additional measures are required with a clozapine prescription?

Answer 7

Due to the risk of agranulocytosis it is required that patients on clozapine have weekly blood tests for the first six months of prescription followed by fortnightly blood tests for the next six months

Question 8

How long should prophylaxis be given after a schizophrenic episode?

Answer 8

Lifelong prophylaxis required

Question 9

What are the potential serious adverse events that are associated with antipsychotics?

Answer 9

Tardive dyskinesia

Neuroleptic malignant syndrome

Extrapyramidal side effects- acute dystonia, parkinsonism syndrome, akathisia

Question 10

What drugs can be given to reduce extrapyramidal side effects?

Answer 10

Anticholinergics (benztropine etc)

Dopamine facilitators (Amantadine)

Beta-blockers (propranolol)

Question 11

What is akathisia?

Answer 11

Characterised by a feeling of inner restlessness and inability to stay still and is associated with an increased risk of suicide