A drug given for metoclopramide induced dystonic reaction is :: (A) Pheniramine, (B) Promethazine, (C) Chlorpromazine, (D) Prochlorperazine
Answer is B. "Acute muscle dystonia caused by antiemetic-antipsychotic drugs is promptly relieved by parenteral promethazine or hydroxyzine." This is based on the central anticholinergic action of the drugs.
Promethazine is a first-generation anti-histaminic which has a maximum penetration of blood-brain barrier and maxi­mum anticholinergic activity.