Parkinson Disease and Psychosis

Question 1

Which receptor mediate CNS dopaminergic pathway, and to what protein is coupled?

Answer 1

D2-like - Gi coupled
D2A - nigrostriatal
D2C - mesolimbic

Question 2

Antipsychotics with less probability to cause extrapyramidal symptoms

Answer 2

Clozapine (block D2C and 5HT2 receptors), Olanzapine (block 5HT2 receptor)

*Atypical antipsychotics

Question 3

Most likely antipsychotic that cause EPS, Tardive dyskinesia and neuroleptic malignant syndrome

Answer 3

Haloperidol

Question 4

Which antipsychotic most likely cause agranulocytosis?

Answer 4

Clozapine

Question 5

Antipsychotic associated with cardiotoxicity (torsades)

Answer 5

Thioridazine

*forms metabolites that block K+ channels ▶️ prolong QT interval

Question 6

Mechanism of action of Aripripazole

Answer 6

Partial agonist D2 receptors

Also blocks 5HT2 receptors

Question 7

Treatment for neuroleptic malignant syndrome

Answer 7

Dantrolene, bromocriptine (DA agonist)