Therapy of angina pectoris with long-acting nitrates: which agent and when?

Nitroglycerin and the long-acting nitrates are effective antianginal agents that have been used in clinical medicine for over 100 years. These drugs are reliable, safe, familiar to clinicians, inexpensive, and easy to use. Side effects are limited to headache and postural hypotensive symptoms. Nitrate tolerance or attenuation, -ie, loss of, or decrease in, nitrate efficacy with repeated dosing-is common and represents the major drawback to chronic therapy. Carefully designed dosing regimens and/or appropriate use of nitrate formulations (to include a nitrate-free period each day) will decrease or eliminate the problem of nitrate tolerance. In head-on comparative studies, nitrates appear to be as effective as beta-blockers or calcium channel blockers in the monotherapy of chronic angina. Ideal patient characteristics for nitrate therapy include: predictably favourable response of chest pain to sublingual nitroglycerin; angina episodes suggestive of coronary vaso-constriction or spasm; left ventricular systolic dysfunction; symptoms of congestive heart failure (systolic or diastolic dysfunction).