Bornaprolol is norbornyl derivative. It is the beta-adrenoceptor blocking agent. The prolonged beta-blocking action of bornaprolol was related to a tight irreversible binding to beta-receptors rather than to pharmacokinetic properties of this drug. In vitro, bornaprolol inhibits isoproterenol-induced stimulation of adenylate cyclase in rat heart homogenate. A dose-related inhibition of the rise in heart rate and blood pressure on sub-maximal exercise 2 h after single doses of bornaprolol. Bornaprolol eliminated mainly by metabolism with a bioavailability that decreases inversely with oral dose. Bornaprolol has a more prolonged action and may prove to be of therapeutic value in situations, such as angina and certain arrhythmias, where sustained high degrees of beta-adrenergic receptor blockade are beneficial. Bornaprolol behaved in man as a non-cardioselective drug.