Sustained anti-anginal action of glyceryl trinitrate cream.

In an acute study, 45 min following topical application of 9.2 mg of nitroglycerin (GTN) cream, exercise time increased by 100s ( < 0.005) and this increase persisted for 270 min. Systolic blood pressure showed a progressive fall. In the second study 1 h following application of 9.2 mg GTN cream, a significant reduction in left ventricular diastolic dimension was seen. In a subsequent chronic randomised double blind study, exercise time increased by 47 s ( < 0.05) at 6 h, following 3 weeks continual use. An increased dose for a further 3 weeks produced no further increase in exercise time; however, a significant decrease in left ventricular end diastolic dimension was seen. No evidence of pharmacological tolerance was seen, as patients continued to show a maximal response to sublingual nitroglycerin during the course of the study.