This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
Drug of choice for thyroid storm is: March 2008 
Select and explain. 
A. Thiocayanates, B. Perchlorates, C. Propylthiouracil, D. Radioactive iodine
C: Propylthiouracil
Answer: C: Propylthiouracil 
Explanation: Ans. C: Propylthiouracil Propylthiouracil is used in thyroid storm for its inhibitory action on peripheral conversion of T4 to more active T3. It is also used in patients developing adverse effects with carbimazole.