Antipsychotics - First generation

Question 1

What are examples of first generation antipsychotics?

Answer 1

• Haloperidol
• Chlorpromazine
• Prochlorperazine

Question 2

What are indications for the use of first generation antipsychotics?

Answer 2

• Severe psychomotor agitation
• Schizophrenia
• Bipolar Disorder
• Nausea and vomiting

Question 3

What is the mechanism of action of first generation antipsychotics?

Answer 3

Block post-synaptic D2 receptors. There are 3 doapminergic pathways:

1. Mesolimbic/mesocortical pathway - runs between midbrain and limbic system/frontal cortex
2. Nigrostriatal pathway - connects substantia nigra with corpus striatum of the basal ganglia.
3. Tuberohypophyseal pathway - connects hypothalamus with pituitary gland.

D2 receptors are also found in the CTZ - blockade helps nausea and vomiting

Question 4

What are side effects of first generation antipsychotics?

Answer 4

• Extrapyramidal side effects
  
  • Dystonia
  • Akasthisia
  • Neuroleptic malignant syndrome
  • Tardive dyskinesia
• Drowsiness
• Hypotension
• QT-prolongation
• ED
• Hyperprolactinaemia

Question 5

WHy does hyperprolactinaemia occur with first generation antipsychotics?

Answer 5

Due to tuberophyseal D2 blockade

Question 6

Why do extrapyramidal side effects occur with first-generation antipsychotics?

Answer 6

D2 blockade in the nigrostriatal pathway

Question 7

What side effect can occur with chronic first generation antipsychotic use?

Answer 7

Tardive dyskinesia

Question 8

What monitoring would you perform on someone using first generation antipsychotics?

Answer 8

• Symptom review
• Signs of neurological, respiratory or CV depression

Question 9

What are examples of high-potency first generation anti-psychotics?

Answer 9

Haloperidol

Question 10

What are examples of extrapyramidal side effects seen with first generation antipsychotic use?

Answer 10

• Tardive dyskinesia
• Neuroleptic malignant syndrome
• Akasthisia
• Acute dystonia

Question 11

What mnemonic can you use to remember the features of neuroleptic malignant syndrome?

Answer 11

FALTER:

• Fever
• Autonomic instability
• Leukocytosis
• Tremor
• Elevated enzymes (creatinine kinase, transaminases)
• Rigor