2. Methods: A convenience sample of patients presenting to the Emergency Department will be randomized to receive either sublingual 0.4 mg doses of nitroglycerin or placebo. Pain prior to and at two minutes and five minutes after medication administration will be assessed using a visual analog scale. The medication will be either a 0.4 mg dose of nitroglycerin or a placebo. If pain is not completely relieved within five minutes, a second dose will be administered after blood pressure assessment. If the pain is not completely relieved after an additional two minute and five minute assessment or the pain returns, it will be treated in the standard manner at the discretion of the treating Emergency Physician. Ancillary studies and other treatments will be at the discretion of the treating physician. The 0.4mg dose of nitro has been proven to be a safe and well tolerated dose when administered to our patient population in treatment of acute coronary syndrome or suspected angina. Our attending, resident, and nursing staff are very familiar with this dose, the potential side effects of the medication, and its administration procedure. Therefore, we believe that 0.4mg will be a optimal starting dose for enrollees in our study.