Typical Antipsychotics

Question 1

What are the common indications for typical antipsychotics?

Answer 1

Urgent treatment of severe psychomotor agitation that is causing dangerous or violent behaviour, or to calm patients to permit assessment.

• *Schizophrenia**, particularly when the metabolic side effects of second-generation (atypical) antipsychotics are likely to be problematic.
• *Bipolar disorder,** particularly in acute episodes of mania or hypomania.
• *Nausea and vomiting**, particularly in the palliative care setting.

Question 2

How do typical antipsychotic drugs work?

Answer 2

Antipsychotic drugs block post-synaptic dopamine D2 receptors

Mesolimbic/mesocortical pathway = antipsychotic effects

Nigrostriatal pathway = Extrapyramidal effects

Tuberohypophyseal pathway = Hyperprolactinaemia effects

Chemoreceptor trigger zone = antiemitic effects

Question 3

What are the extrapyramidal side effects caused by typical sntipsychotics?

Answer 3

Acute dystonia

Akathisia

Neuroleptic malignant syndrome

Tardive dyskinesia

Question 4

What are the features of neuroleptic malignant syndrome?

Answer 4

A rare but life-threatening side effect characterised by rigidity, confusion, autonomic dysregulation and pyrexia.

Question 5

What are the other adverse effects of typical antipsychotics?

Answer 5

Drowsiness

Hypotension

QT-interval prolongation (and consequent arrhythmias)

Erectile dysfunction

Hyperprolactinaemia effects: menstrual disturbance, galactorrhoea and breast pain

Question 6

Which patients require extra consideration when prescribing?

Answer 6

Elderly - usually very sensitive and therefore require smaller doses

Should be avoided in dementia as it increases risk of death and stroke

Should be avoided in patients with parkinsons due to their extrapyramidal side effects

Care should be taken when prescribing for patients on drugs that cause QT elongation (amiodarone and macrolides)

Question 7

What is often a first line choice for acute or violent bevahior?

Answer 7

Haloperidol

Question 8

What kind of arrhythmia may develop when antipsychotics are given by injection or high dose?

Answer 8

Torsades de pointes

Question 9

What are potential treatments for intractable hiccups?

Answer 9

Haloperidol

Chlorpromazine

Metoclopramide

Question 10

Give examples

Answer 10

haloperidol, chlorpromazine, prochlorperazine