Glyceryl Trinitrate in Angina Pectoris: Tablet or Aerosol ?

Abstract

A controlled double-blind objective evaluation of the use of an aerosol preparation of glyceryl trinitrate was made in 23 patients with typical angina pectoris, and the results are compared with a standard 0.5-mg. tablet of glyceryl trinitrate administered sublingually. Assessment was made by exercise-tolerance tests with continuous radiocardiographic monitoring during and after exercise, as well as a conventional pre- and post-exercise electrocardiogram. The dose of aerosol studied was 0.26 mg. delivered in two inhalations, and both aerosol and tablet preparations were assessed before and after exercise. The active aerosol was no more effective than the placebo aerosol in favourably influencing the amount of exercise performed, the incidence and duration of angina, or the degree and duration of the ischaemic change in the electrocardiogram these results applied to administration both before and after exercise. On the other hand, glyceryl trinitrate tablets significantly improved ischaemic changes in the electrocardiogram when given before exercise, but not when given after it. It is concluded that the aerosol preparation of glycerol trinitrate used in the present trial is ineffective, and prophylactic sublingual administration of glyceryl trinitrate tablets still remains the treatment of choice. © 1967, British Medical Journal Publishing Group. All rights reserved.