This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: CHF, Angina Pectoris and Myocardial Infarction, Subject name: Pharmacology
Which of the following drug is contraindicated in variant angina? 
Select and explain. 
A. Diltiazem, B. Nitrates, C. Propranolol, D. Verapamil
C: Propranolol
Answer: C: Propranolol 
Explanation: Variant angina is caused by coronary vasospasm DOC:Sublingual Nitroglycerine Prophylaxis : Calcium channel blockers (like verapamil and Diltiazem) and nitrates Beta blockers are avoided as they may precipitate coronary vasospasm by counteracting beta 2 mediated coronary vasodilation. Therefore they are avoided in variant angina.