Katzung 13th ed - Chapter 29 - Antipsychotics (2)

Question 1

There are two classes of CNS receptors that are stimulated to produce psychosis, and are antagonized by the atypical antipsychotics to prevent psychosis. Which two are these?

Answer 1

Serotonin (5HT2A) receptors and Dopamine (D2) receptors.

Question 2

Name two classical (typical) antipsychotics that are still in common use today.

Answer 2

Haloperidol
Chlorpromazine (Largactil)

Question 3

What is the key pharmacodynamic feature of the atypical antipsychotics that causes prevention of psychosis?

Answer 3

5HT2A receptor blockade.

Question 4

What is the key difference in the pharmacodynamic features of typical and atypical antipsychotics, in their mechanism of preventing psychosis?

Answer 4

Typical antipsychotics:
D2 receptor blockade is greater than 5HT2A receptor blockade
Atypical antipsychotics:
5HT2A receptor blockade is greater than D2 receptor blockade

Question 5

Name some atypical antipsychotics.

Answer 5

Clozapine
Risperidone
Olanzapine
Quetiapine
Aripiprazole

Question 6

Name some receptors that are antagonized by atypical antipsychotics.

Answer 6

5HT2A (serotonin)
D2 (dopamine)
Alpha-1 (adrenaline)
Alpha-2
H1 (histamine)
Muscarinic (acetylcholine)

Question 7

Name some of the extrapyramidal side effects.

Answer 7

Akathisia
Parkinsonism
Tardive dyskinesia
Dystonia
Autonomic effects

Question 8

Which antipsychotic has the highest extrapyramidal toxicity?

Answer 8

Haloperidol

Question 9

What is the pharmacodynamic feature of antipsychotics that causes extrapyramidal side effects?

Answer 9

D2 receptor blockade.

Question 10

Describe the adverse effects of antipsychotics.

Answer 10

EPS
Anticholinergic symptoms
Alpha-1 antagonism: postural hypotension, tachycardia
Neuroleptic malignant syndrome

Question 11

What are the features of Neuroleptic Malignant Syndrome?

Answer 11

Muscle rigidity
Fever
Autonomic instability
Reduced sweating

Question 12

Describe some basic pharmacokinetics of antipsychotics.

Answer 12

Lipid soluble, highly protein bound (95%), large volume of distribution. Long half-lives. Metabolized in liver and excreted in urine.

Question 13

What is the most common clinical indication for lithium?

Answer 13

Bipolar affective disorder

Question 14

What are some basic pharmacokinetics of lithium?

Answer 14

Bioavailability: 100%
Peak plasma levels in 30 mins - 2hrs.
Distributed in total body water.
Zero metabolism.
Excreted entirely in urine.