Propranolol LA and ambulatory blood pressure.

1 The technique of continuous recording of intra-arterial blood pressure in ambulant hypertensives has been used to investigate the effects of a long-acting formulation of propranolol (propranolol LA). 2 Seven subjects with untreated essential hypertension were studied before and 2 months after commencing treatment with propranolol LA once daily in the morning, results showing that smooth control of blood pressure and heart rate occurred throughout 24 h. 3 Bicycle ergometry tests performed by these subjects during both studies showed significant blood pressure reduction by propranolol LA during the mild and moderate grades of dynamic exercise. 4 In a parallel study where six treated hypertensives were monitored before and after substitution of standard propranolol by the 'LA' form, close correspondence of blood pressure throughout the 24 h occurred with each regimen.