NITROGLYCERIN, which was first synthesized in 1846 and known as glonoine, was initially employed by homeopathic physicians to treat headaches and palpitations.¹ Sir Lauder Brunton² reported on the use of amyl nitrite in 1867, and in 1879, William Murrell³ described the beneficial effects of nitroglycerin in patients with angina pectoris. Several organic nitrates with various formulations are currently available, but controversy has arisen regarding their clinical efficacy and the fact that during sustained therapy, the effects of the nitrates are substantially diminished as compared with their short-term effects. Attenuation of the antianginal effects during sustained therapy suggests that nitrate tolerance . . .