BLOOD-LEVELS, TISSUE DISTRIBUTION AND THE DURATION OF ACTION IN RATS OF CIPROFIBRATE - NEW HYPOLIPIDEMIC AGENT

The blood levels, distribution and duration of action of ciprofibrate, an orally active hypolipidemic agent, was investigated in rats. Serum concentrations of 30 μg of ciprofibrate/ml are associated with significant reductions in both serum cholesterol and triglycerides in rats on a hyperlipidemic diet. Increasing the plasma concentrations of ciprofibrate to 69 μg/ml resulted in only a modest incremental reduction in serum lipids. The distribution of radioactivity from [14C] ciprofibrate within rat tissues was not affected by prior treatment for 14 days with ciprofibrate at either 1.5 or 3.0 mg/kg/day. Varying the dosage regimen of ciprofibrate at 30 mg/kg, with medication at intervals of one, 2 or 3 days resulted in similar peak plasma levels of about 300 μg/ml, 4 h after medication. The half-life of ciprofibrate, during the terminal disposition phase, was about 82 h. Levels of serum cholesterol remained suppressed up to 3 days after medication with ciprofibrate was discontinued; triglyceride levels returned to control values more slowly. © 1979.