title: Transdermal nitroglycerin in angina pectoris: efficacy of intermittent application.
abstract: Continuous application of transdermal nitroglycerin appears to result in tolerance to the antianginal effect. In a double-blind study the effects of continuous (24 h/day) and intermittent (16 h/day) application of transdermal nitroglycerin in a dosage of 10 mg/day were compared with the effects of placebo in 12 patients with chronic stable angina receiving treatment with beta-adrenergic blocking or calcium channel blocking agents. Exercise performance was assessed 2 to 4 hours after initial application and after 1 week of each treatment given in random order with a 3 day interval between treatments. Exercise time to onset of angina, total exercise duration and time to 1 mm ST segment depression were all significantly increased after initial application during the continuous and intermittent treatment periods. These increases were maintained after 1 week of intermittent but not continuous treatment. Thus the benefit of initial application of transdermal nitroglycerin is maintained with intermittent treatment and a daily nitrate-free interval, whereas tolerance to antianginal effect occurs with continuous treatment.
mesh_terms: D000279:Administration, Cutaneous; D000328:Adult; D000368:Aged; D000787:Angina Pectoris / Q000188:drug therapy* / Q000503:physiopathology; D005080:Exercise Test; D006261:Headache / Q000139:chemically induced; D006801:Humans; D008297:Male; D008875:Middle Aged; D005996:Nitroglycerin / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use
chemical_list: D005996:Nitroglycerin