Disposition of 3-hydroxyquinidine in patients receiving initial intravenous quinidine gluconate for electrophysiology testing of ventricular tachycardia.
The formation rate constant and elimination rate constant for 3-hydroxyquinidine were determined in eight patients with ventricular tachycardia. These two parameters (mean +/- SD) were found to be 0.784 +/- 0.202 and 0.042 +/- 0.058 h-1, respectively. Coefficients of determination for the computer-generated line of best fit for serum concentration-time data were 0.986 +/- 0.008. Patients received two infusions of quinidine gluconate 5 mg/kg over 30 minutes separated by a 20-30 minute electrophysiologic testing period. Unbound and total 3-hydroxyquinidine concentrations were also determined. Among the eight patients, 3-hydroxyquinidine was 61.9 percent bound. Studies in healthy volunteers had shown 50 percent binding. Linear regression of unbound and total 3-hydroxyquinidine was described by the equation Y = 0.3814X-1.448, r = 0.813. Although half-lives of 3.5-12.4 hours had been reported in healthy volunteers, prolonged half-lives were observed in all but two of our arrhythmia patients.
Ackerman
B H
BH
Department of Pharmacy Practice, College of Pharmacy, University of Arkansas for Medical Sciences, Little Rock 72205.
Olsen
K M
KM
Kennedy
E E
EE
Taylor
E H
EH
Chen
B H
BH
Jordan
D
D
Ackerman
D J
DJ
D000328:Adult; D000368:Aged; D000889:Anti-Arrhythmia Agents / Q000008:administration & dosage / Q000493:pharmacokinetics*; D004594:Electrophysiology; D005260:Female; D006207:Half-Life; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D008875:Middle Aged; D011802:Quinidine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000493:pharmacokinetics / Q000627:therapeutic use; D013610:Tachycardia / Q000503:physiopathology*
D000889:Anti-Arrhythmia Agents; C013569:3-hydroxyquinidine; D011802:Quinidine; C016713:quinidine gluconate