Kendall M J, Maxwell S R, Sandberg A, Westergren G
Department of Medicine, Queen Elizabeth Hospital, Birmingham, England.
Clin Pharmacokinet. 1991 Nov;21(5):319-30. doi: 10.2165/00003088-199121050-00001.
Metoprolol is a relatively beta 1-selective beta-blocker used extensively to treat hypertension and angina and as a prophylaxis after myocardial infarction. Conventional formulations are usually administered twice daily and the drug has a tendency to lose its selectivity of action at higher plasma concentrations. Two controlled release formulations, metoprolol CR and metoprolol 'Oros', have made it possible to achieve sustained beta 1-blockade over an entire 24h period and to minimise the loss of selectivity associated with higher plasma concentrations. The CR formulation has been extensively investigated and is the major subject of this review. The 'Oros' formulation is pharmaceutically different from the CR, yet both produce similar plasma concentration profiles and comparable beta 1-blocking effects. The availability of these preparations occurs at a time when increasingly persuasive data are becoming available on the cardioprotective or coronary preventive action of metoprolol.
美托洛尔是一种相对β1选择性β受体阻滞剂，广泛用于治疗高血压和心绞痛，并作为心肌梗死后的预防用药。传统剂型通常每日给药两次，且该药物在较高血浆浓度时往往会失去其作用选择性。两种缓释剂型，即美托洛尔控释片和美托洛尔“渗透泵片”，使得在整个24小时内实现持续的β1受体阻滞成为可能，并将与较高血浆浓度相关的选择性丧失降至最低。控释片剂型已得到广泛研究，是本综述的主要主题。“渗透泵片”剂型在药学上与控释片不同，但两者产生相似的血浆浓度曲线和相当的β1受体阻滞作用。这些制剂上市之时，关于美托洛尔的心脏保护或冠心病预防作用的越来越有说服力的数据也日益可得。
