The effects of oxprenolol (Trasicor, Ciba 39089-Ba) on patterns of urinary sodium excretion in man

Abstract

The effects of oxprenolol (Trasicor, Ciba 39089-Ba) on patterns of sodium excretion were evaluated in normal subjects and in patients with cardiac disease. In normal subjects 120 mg of oxprenolol daily caused a slight but significant increase in sodium excretion, and the day/night sodium excretion ratio was reversed in 60 percent. With doses of 240 mg, the sodium excretion in these subjects fell to control levels, but the excretion ratio was reversed in all. In patients with cardiac disease with incipient failure sodium was not retained during treatment with either 120 mg or 240 mg of oxprenolol daily. In 1 patient with ischemic heart disease receiving 120 mg of propranolol daily sodium was retained and frank heart failure was precipitated whereas 240 mg of oxprenolol produced no change. Differences between oxprenolol and propranolol in antagonizing beta receptor excitation and depressing myocardial contractility are discussed. The direct negative inotropic action of this group of drugs may also contribute to the changes in patterns of sodium excretion induced by beta receptor blockade.