This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Histamine, 5-HT and PGs, Subject name: Pharmacology
The drug of choice for prophylaxis of motion sickness is:- 
Select and explain. 
A. Promethazine, B. Ondansetron, C. Metoclopramide, D. Domperidone
A: Promethazine
Answer: A: Promethazine 
Explanation: (Best Drug)Doc for prophylaxis of motion sickness - Hyoscine (scopolamine) If hyoscine is not given in the option, then the answer would be first generation Antihistaminics. First generation Antihistaminics can cross the blood brain barrier and also have strong Anti-cholinergic propeies. First generation Antihistaminics - Promethazine