This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cardiovascular system, Subject name: Pharmacology
Nitrites are used for all of the following conditions except? 
Select and explain. 
A. Congetive hea failure, B. Cyanide Poisoning, C. Esophangeal spasm, D. Renal colic
D: Renal colic
Answer: D: Renal colic 
Explanation: Nitrates are used in angina, congestive cardiac failure, biliary colic, cyanide poisoning. Not in renal colic. used only in biliary colic due to the sphincter spasm They cause smooth muscle relaxation including endothelium of veins-venous dilation. so used in all above-mentioned conditions. REF.Essentials of Pharmacology KD Tripathi 8th ed.