Changes in Plasma Volume and Extracellular Fluid Volume after Addition of Hydralazine to Propranolol Treatment in Patients with Hypertension

Abstract

ABSTRACT. In 16 patients with hypertension, BP could not be controlled satisfactorily by treatment with propranolol alone (mean dosage 325 mg/day). Plasma volume (PV) (T‐1824) and extracellular fluid volume (ECV) (82Br‐distribution space) were determined in these patients before and after the addition of hydralazine for three months (mean dosage 135 mg/day). After the addition of hydralazine, PV and ECV increased significantly, by 9% and 3%, respectively. Systolic and diastolic BPs decreased, by 15% and 13%. The mechanisms inducing fluid retention during treatment with hydralazine and the clinical significance of the problem are discussed. It is concluded that the addition of a diuretic to propranolol‐hydralazine treatment is often well indicated.

Calcium Blockade as a Therapeutic Principle in Arterial Hypertension: Clinical aspects and experimental studies on isolated vessels from spontaneously hypertensive rats and normotensive man.

“…During long-term treatment with potent vasodilatators, fluid retention is often a problem (Finnerty et al, 1970), especially when combined with beta-adrenoceptor blocking drugs (Ibsen et al, 1978). In the present studies, we found no clinical evidence of fluid retention during nifedipine monotherapy for 4-6 weeks nor on combi-nation with beta-adrenoceptor blockers for 4 weeks (VIII, X).…”