Douchamps J, Derenne F, Stockis A, Gangji D, Juvent M, Herchuelz A
Unité de Pharmacologie Clinique, Hôpital Vésale, Montigny-le-Tilleul, Belgium.
Eur J Clin Pharmacol. 1988;35(5):515-20. doi: 10.1007/BF00558247.
We have studied the pharmacokinetics of oxybutynin (Ditropan) after single oral (5 mg) and intravenous administration (1 and 5 mg), and after repeated oral administration in healthy volunteers. Oxybutynin was rapidly absorbed, maximum plasma concentrations (8 ng.ml-1) being reached in less than 1 h. The absolute systemic availability averaged 6% and the tablet and solution forms displayed similar relative systemic availability. Plasma concentrations of oxybutynin fell biexponentially, the elimination half-life being about 2 h. There was a large interindividual variation in oxybutynin plasma concentrations. Almost no intact drug could be recovered in the urine. During repeated oral administration steady-state was reached after eight days of treatment. The low absolute systemic availability of oxybutynin, the large interindividual variability in its plasma concentrations, and the apparent absence of intact oxybutynin in the urine suggest that its major pathway of elimination is hepatic metabolism.
我们研究了奥昔布宁（得妥）在健康志愿者单次口服（5毫克）和静脉注射（1毫克和5毫克）后以及多次口服后的药代动力学。奥昔布宁吸收迅速，在不到1小时内达到最大血浆浓度（8纳克/毫升）。绝对全身生物利用度平均为6%，片剂和溶液剂型显示出相似的相对全身生物利用度。奥昔布宁的血浆浓度呈双指数下降，消除半衰期约为2小时。奥昔布宁血浆浓度存在较大的个体间差异。尿液中几乎无法回收完整的药物。在多次口服给药过程中，治疗八天后达到稳态。奥昔布宁的绝对全身生物利用度低、血浆浓度个体间差异大以及尿液中明显不存在完整的奥昔布宁，表明其主要消除途径是肝脏代谢。
