Improvement in exercise tolerance and immediate beta-adrenergic blockade with intranasal propranolol in patients with angina pectoris

Abstract

A new intranasal spray formulation of propranolol was developed to provide β-adrenergic blocking medication on an immediate basis to patients with angina pectoris. The effects of this spray or placebo were assessed in 16 patients with effort-induced angina in a blinded, randomized, crossover design study that compared placebo with intranasal propranolol spray (5 mg/puff) 15 minutes before exercise on a treadmill (Bruce protocol). One week later, each patient, acting as his/ her own control, received the alternative treatment and repeated exercise. Mean plasma propranolol level with active therapy was 20 ng/ml. Patients with active spray demonstrated a significant increase in total exercise time than patients taking placebo (530 ± 197 vs 460 ± 177 seconds, p = 0.05), an increase in the time to 1 mm ST-segment depression on the electrocardiogram (384 ± 202 vs 327 ± 144 seconds, p <0.05), and an increase in time to onset of angina (452 ± 149 vs 363 ± 175 seconds, p = 0.0005). There was a blunting of maximal exercise heart rate with active therapy compared with placebo (120 ± 13 vs 133 ± 17 beats/min, p <0.01), blunting of maximal exercise systolic blood pressure (185 ± 22 vs 194 ± 21 mm Hg, p < 0.05), and blunting of peak double product (p < 0.0005), with more modest effects on resting heart rate. Propranolol spray is an effective approach for providing immediate β blockade and improving exercise tolerance in patients with angina pectoris.