Influence of nisoldipine on haemodynamic effects and plasma levels of digoxin.

Abstract

In a placebo controlled double‐blind study including 10 patients with heart failure the nisoldipine/digoxin interaction was studied. Nisoldipine was shown to elevate digoxin plasma concentrations significantly by about 15% (trough levels). During chronic combination therapy with nisoldipine trough levels and plasma concentrations 4 h after the morning dose of digoxin were 1.35 +/‐ 0.14 and 1.92 +/‐ 0.16 ng ml‐1 respectively, whereas they averaged to 1.16 +/‐ 0.14 and 1.52 +/‐ 0.16 ng ml‐1 with digoxin and placebo (P less than 0.05; mean +/‐ s.e. mean). Systolic time intervals were significantly altered by nisoldipine co‐administration compared with digoxin plus placebo. In certain patients the elevation of digoxin plasma levels due to nisoldipine co‐administration could be of clinical relevance. 1986 The British Pharmacological Society