Effects of sustained intravenous diltiazem infusion in healthy persons.
A 3-stage infusion of diltiazem was tested in 8 subjects for up to 48 hours: a bolus injection (10 mg over 3 minutes), a rapid loading infusion (20 mg over 30 minutes) and a maintenance infusion (10 mg/hour to the end of the study). This regimen produced stable median plasma diltiazem concentrations of approximately 150 ng/ml. The median half-life of elimination for diltiazem was 206 minutes (range 144 to 452) and median total clearance was 980 ml/min (range 665 to 1,907). The PR interval lengthened 10 to 18% during the maintenance infusion in 7 subjects; in 1 subject atrioventricular nodal Wenckebach conduction was recorded during the rapid loading infusion. Systolic blood pressure decreased from 124 +/- 7 mm Hg (mean +/- standard deviation) during the control period to 121 +/- 8 mm Hg during the rapid loading infusion (p = 0.03 compared with control) and to 117 +/- 7 mm Hg (p = 0.04 compared with control) during the maintenance infusion. Heart rate did not change. PR interval and blood pressure returned to control levels within 4 hours after the infusion was stopped. Loading and maintenance infusion may be an attractive method of administering diltiazem when stable drug concentrations are required for prolonged periods.
D000328:Adult; D001283:Atrioventricular Node / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects; D004110:Diltiazem / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000097:blood*; D004562:Electrocardiography; D006801:Humans; D007262:Infusions, Intravenous; D007700:Kinetics; D008297:Male
C037769:deacetyldiltiazem; D004110:Diltiazem