MONONITRATES - DEFINING THE IDEAL LONG-ACTING NITRATE

As a result of recent advances in our understanding of the role of nit ric oxide and endothelial-derived relaxing factor (EDRF) in vascular c ontrol, physicians now have the potential to overcome the loss of EDRF effect by administering nitrates. Nitrates are converted to nitric ox ide, resulting in vasodilator effects that improve the myocardial oxyg en supply-demand imbalance responsible for myocardial ischemia. This d iscovery has resulted in a renewed interest in the nitrates for the tr eatment of ischemic syndromes, particularly chronic stable angina pect oris. Over the past 2 years, an important new formulation of nitrate h as become available-isosorbide-5-mononitrate. Three different mononitr ate formulations are available in the United States: Ismo(R) tablets i n December 1992; followed over a year later by Monoket(R) tablets, ava ilable since June 1993; and Imdur(TM) extended-release tablets, availa ble since August 1993. Although the mononitrates share the same generi c name, they are not similar in regard to their formulations, which su ggests the need for future studies designed to explore any clinical di fferences.