A study of cross‐tolerance to circulatory effects of organic nitrates

Abstract

Ten hospitalized volunteer subjects were given pentaerythrol tetra nitrate (PETN) daily in divided doses over a period of four weeks. Before and during PETN treatment, the subjects were challenged with 0.3 mg. sublingual nitroglycerin (NTC). The changes in blood pressure and heart rate after NTC were significantly decreased while subjects were receiving PETN. Reports of NTC‐ and PETN‐related headache also decreased during PETN administration. Since long‐acting nitrates may carry within them the seeds of their own therapeutic failure via the development of tolerance, it is suggested that animal studies on such agents routinely include repeated pharmacological testing designed to detect and measure the development of tolerance to cardiovascular and other effects.