The pharmacokinetics of the new beta-adrenoceptor blocking drug bevantolol and some aspects of its beta-blocking effect have been studied in healthy volunteers. Bevantolol had a short serum half-life (86 +/- 33 min) and high systemic availability after oral administration. The observed changes in heart rate, systolic blood pressure during exercise and plasma renin activity were all compatible with beta-adrenoceptor blockade. After 200 mg p.o. in the morning, the effects lasted for less than 24 h.