Bevantolol: A Beta‐1 Adrenoceptor Antagonist with Unique Additional Actions

UNLABELLED: Bevantolol is a beta-1 adrenoceptor antagonist that has been shown to be as effective as other beta blockers for the treatment of angina pectoris and hypertension. Some interesting additional properties, such as the absence of the side effect of cold extremities, required investigation, and a great deal of new evidence has been accumulated during the last three years. This new data is consistent with the proposal put forward a couple of years ago that bevantolol interacts with alpha-adrenoceptors. All the available evidence, published and unpublished, has been reviewed and fits into a coherent pattern, here arranged into five sections. Chemistry: affinity for alpha-adrenoceptors. Animal experiments confirm both agonist and antagonist effects on alpha-receptors, in addition to antagonist activity at beta-1 receptors. In addition, bevantolol has electrophysiologic effects, including bradycardia by a direct action on the sinus node and a class 1 antiarrhythmic action. Investigations in humans have shown that although bevantolol has a short half-life, good control of hypertension can be achieved on once-a-day dosing. SAFETY: bevantolol has remarkably few side effects, does not cause cold extremities, and does not significantly affect glomerular filtration rate in patients with renal impairment. Evidence has been obtained in man for interaction with alpha-adrenoceptors in the brain; and in the peripheral circulation bevantolol does not, as do other beta blockers, increase peripheral vascular resistance, but reduces it. It is suggested that all the additional actions of bevantolol can be attributed to a partial agonist action on alpha-adrenoceptors.