Morgan T
Department of Physiology, University of Melbourne, Heidelberg, Victoria, Australia.
Clin Pharmacokinet. 1994 May;26(5):335-46. doi: 10.2165/00003088-199426050-00002.
Carvedilol is an arylethanolamine that is a racemic mixture of 2 enantiomers. The S-(-)-enantiomer has beta-adrenoceptor blocking activity, while the racemate also has alpha 1-receptor blocking activity due to the activity of the R-(+)-enantiomer. The drug is rapidly absorbed and undergoes extensive first-pass metabolism in the liver. It reaches a peak concentration 1 to 2 hours postdose and has an elimination half-life of about 4 to 7 hours. Absorption is delayed by food. The drug is highly lipophilic and is highly protein bound. The drug is metabolised by the liver, with some metabolites having biological activity. The pharmacokinetic profile is not altered in the elderly or in patients with renal disease. However, bioavailability of the oral medication is greatly increased in patients with liver disease. Carvedilol lowers blood pressure as a result of its beta-blocking and vasodilatory activity. The reduction in blood pressure is similar to that achieved with other antihypertensive drugs, and there are no adverse effects on renal or cerebral blood flow. Carvedilol has been used in small numbers of patients with cardiac failure. It reduces left ventricular hypertrophy and has no significant adverse metabolic effects.
卡维地洛是一种芳基乙醇胺，是由2种对映体组成的外消旋混合物。S-(-)-对映体具有β-肾上腺素受体阻断活性，而外消旋体由于R-(+)-对映体的活性也具有α1受体阻断活性。该药吸收迅速，在肝脏中经历广泛的首过代谢。给药后1至2小时达到峰值浓度，消除半衰期约为4至7小时。食物会延迟吸收。该药具有高度脂溶性，且与蛋白质高度结合。该药在肝脏代谢，一些代谢产物具有生物活性。老年人或肾病患者的药代动力学特征未改变。然而，肝病患者口服药物的生物利用度会大大提高。卡维地洛因其β阻断和血管舒张活性而降低血压。血压降低程度与其他抗高血压药物相似，对肾或脑血流无不良影响。卡维地洛已用于少数心力衰竭患者。它可减轻左心室肥厚，且无明显不良代谢影响。
