Pharmacokinetics of amiodarone in rats.
We studied the kinetics of amiodarone in the rat. After an intravenous dose of 50 mg/kg, the time-course of the drug concentrations was assessed by high-pressure liquid chromatography in blood and tissues up to 16 h. The drug disappeared from the blood with an elimination half-life (t1/2beta) of 514 min and distributed extensively into tissues [apparent volume of distribution (Vd)= 29.51 L/kg]. Concentrations were highest in liver, kidney, and heart, and lowest at all times in the brain. The highest concentrations were found within 5-30 min of administration. Amiodarone accumulated extensively in adipose tissue and reached a fat/blood concentration ratio of about 1,000 at 16 h. Single-pass rat liver perfusion experiments gave an hepatic extraction ratio of 0.49 and an intrinsic clearance of 5.48 ml/min. Amiodarone disappearance in rat liver recirculation experiments was biexponential, with a half-life of 58 min.
D000638:Amiodarone / Q000378:metabolism*; D000818:Animals; D001572:Benzofurans / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D006207:Half-Life; D007700:Kinetics; D008099:Liver / Q000378:metabolism; D008297:Male; D051381:Rats
D001572:Benzofurans; D000638:Amiodarone