Pysch - Antipsychotics

Question 1

What are the 2 classes of drug used in schizophrenia?

Give relevant examples

Answer 1

Typical antipsychotics - Haloperidol, Chlorpromazine

Atypical antipsychotics - Olanzapine, Risperidone, Quetiapine, Clozapine

Question 2

What are the major uses of the typical antipsychotics?

Answer 2

• 2nd line treatment of schizophrenia

- Schizophrenic emergencies - Haloperidol

Question 3

What is the mechanism of action of the typical antipsychotics?

Answer 3

Block post-synaptic dopamine D2 receptors, probably particularly in mesolimbic/mesocortical pathways?

Question 4

List some ADRs of the typical antipsychotics

Answer 4

Sedation
Exrapyramidal symptoms
Neuroleptic malignant syndrome
Postural hypotension

Question 5

What is the indication for the atypical antipsychotics?

Answer 5

First-line for treatment of schizophrenia

except Clozapine - 3rd line after typical

Question 6

Why are the atypical antipsychotics preferable to the typical ones?

Answer 6

• Fewer ADRs
• Some can be taken once a day
• Various preparations e.g. dissolvable
• Improved efficacy

Question 7

What is the mechanism of action of the atypical antipsychotics?

Answer 7

Same as typical - bind to dopamine D2 receptors on post-synaptic membrane

Question 8

List 4 ADRs of the atypical antipsychotics

Answer 8

• Sedation

- Metabolic disturbances such as weight gain, diabetes, hyperprolactinaemia

Question 9

List 4 ADRs of Clozapine

Answer 9

Severe constipation
Profound weight gain
Hypersalivation
Severe agranulocytosis

Question 10

List 3 DDIs of all antipsychotics

Answer 10

Sedatives
Dopamine-blocking antiemetics
Drugs that prolong QT interval