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The Medical Journal of Australia Nov 1994
Review
Topics: Adrenergic beta-Antagonists; Drug Interactions; Humans
PubMed: 7968760
DOI: 10.5694/j.1326-5377.1994.tb127604.x -
Trends in Pharmacological Sciences Apr 1994
Topics: Adrenergic beta-Antagonists; Humans; Stereoisomerism; Structure-Activity Relationship
PubMed: 7912460
DOI: 10.1016/0165-6147(94)90044-2 -
The American Journal of Cardiology Nov 1990Beta-adrenergic blockers have been shown definitely to reduce the incidence of total mortality, cardiovascular mortality, sudden death and nonfatal reinfarction in... (Review)
Review
Reduction of mortality, sudden death and non-fatal reinfarction with beta-adrenergic blockers in survivors of acute myocardial infarction: a new hypothesis regarding the cardioprotective action of beta-adrenergic blockade.
Beta-adrenergic blockers have been shown definitely to reduce the incidence of total mortality, cardiovascular mortality, sudden death and nonfatal reinfarction in survivors of an acute myocardial infarction. The mechanisms to explain this protective action of beta blockers have never been elucidated conclusively, and include the antiarrhythmic and myocardial oxygen demand-reducing effects of the drugs. An antithrombotic mechanism has also been suggested. However, beta blockers have relatively weak antiplatelet activity, suggesting that their antithrombotic effects may be related to prevention of coronary artery plaque rupture and the subsequent propagation of an occlusive arterial thrombus rather than direct anticoagulant action. The therapeutic ability of beta blockers to attenuate the hemodynamic consequences of catecholamine surges, may protect a vulnerable atherosclerotic plaque from fracture, thereby reducing risk of coronary thrombosis, myocardial infarction and death.
Topics: Adrenergic beta-Antagonists; Humans; Myocardial Infarction
PubMed: 1978548
DOI: 10.1016/0002-9149(90)90401-l -
The Annals of Pharmacotherapy Jan 1996To compare the similarities and differences among the ocular beta-blockers. Important considerations when comparing these agents are the differences in systemic adverse... (Comparative Study)
Comparative Study Review
OBJECTIVE
To compare the similarities and differences among the ocular beta-blockers. Important considerations when comparing these agents are the differences in systemic adverse effects, local tolerability, and cost.
DATA SOURCE
Information was retrieved from a MEDLINE search of the English-language literature and bibliographic reviews of review articles. Index terms included beta-blockers, glaucoma, timolol, levobunolol, betaxolol, metipranolol, and carteolol.
STUDY SELECTION
Emphasis was placed on eyedrop studies, as well as properly designed and executed clinical trials that assessed dosage, dosing interval, therapeutic response, adverse effects, and cost.
DATA EXTRACTION
Data from several studies were evaluated according to the study design, therapeutic response, and adverse effects.
DATA SYNTHESIS
Timolol maleate, levobunolol, metipranolol, and carteolol have similar effectiveness in lowering intraocular pressure; however, levobunolol and timolol gel forming solution may have an advantage of once-daily dosing. Studies have not been published comparing the clinical efficacy of timolol hemihydrate with that of other ocular beta-blockers. Metipranolol is cost effective in treating primary open-angle glaucoma; however, it has been associated with more ocular burning, stinging, and granulomatous anterior uveitis than other agents. The intrinsic sympathomimetic activity of carteolol has not yet displayed a definite advantage over the other agents in terms of optic disk perfusion and systemic adverse effects. The control of intraocular pressure with betaxolol has not always been as good as with timolol; however, betaxolol has some advantages over timolol and the other topical beta-blockers in terms of systemic adverse effects.
CONCLUSIONS
Considering cost, efficacy, and safety, timolol maleate is the recommended formulary agent because the other agents cannot consistently show an outstanding advantage.
Topics: Adrenergic beta-Agonists; Adrenergic beta-Antagonists; Animals; Epinephrine; Glaucoma; Humans; Intraocular Pressure
PubMed: 8773166
DOI: 10.1177/106002809603000109 -
The American Journal of Cardiology Nov 1983Beta-adrenoceptor antagonists are effective in the management of patients with mild-to-moderate hypertension. Noncardioselective agents, cardioselective agents and beta... (Review)
Review
Beta-adrenoceptor antagonists are effective in the management of patients with mild-to-moderate hypertension. Noncardioselective agents, cardioselective agents and beta blockers with intrinsic sympathomimetic activity (ISA) are equally effective, provided they are used in equipotent doses. Beta blockers can be used as first-line therapy in the management of hypertension and can be safely combined with diuretics, vasodilators, or both, for a better control of blood pressure. The exact mechanism by which beta blockers decrease blood pressure remains speculative, but they all reduce cardiac output during long-term therapy; drugs with ISA lower cardiac output and heart rate less than do drugs without ISA. Pharmacokinetic properties of beta blockers differ widely; drugs metabolized by the liver have shorter plasma half-lives than drugs primarily excreted by the kidneys. Although many of the side effects of various beta blockers are similar, differences in water and lipid solubility account for a higher incidence of central nervous system side effects with lipid-soluble drugs (such as propranolol and metoprolol) than with hydrophilic drugs (such as atenolol and timolol). The incidence of cold extremities has been reported to be less with drugs with ISA, and the incidence of bronchospasm less with cardioselective drugs. In the management of uncomplicated mild-to-moderate hypertension, all beta blockers are equally effective and produce less troublesome side effects than alternative antihypertensive agents. For effective therapy beta blockers can be used in 2 divided daily doses or even once daily.(ABSTRACT TRUNCATED AT 250 WORDS)
Topics: Adrenergic beta-Antagonists; Blood Pressure; Cardiac Output; Central Nervous System; Drug Evaluation; Drug Therapy, Combination; Humans; Hypertension; Kinetics; Vascular Resistance
PubMed: 6139008
DOI: 10.1016/0002-9149(83)90637-9 -
Expert Opinion on Pharmacotherapy Feb 2007The beneficial effects of beta-blocker therapy in patients with heart failure have been consistently shown by multi-center randomised trials. These agents are effective... (Review)
Review
The beneficial effects of beta-blocker therapy in patients with heart failure have been consistently shown by multi-center randomised trials. These agents are effective and also relatively well tolerated in the elderly and in patients with diabetes and advanced heart failure--traditionally considered as relative contraindications to their administration. However, the use of beta-blockers in clinical practice remains low. The difficulties in their initiation and up-titration may be overcome by patient and physician education, as well as by their initiation during hospitalisation and/or the involvement of non-physician providers (i.e., a nurse facilitator). Forthcoming advances in the pharmacokinetic and pharmacodynamic characteristics of some beta-blockers, and testing of novel methods for patient and drug selection may be based on genetic testing, and may allow further improvement of beta-blocker therapy in the next future.
Topics: Adrenergic beta-Antagonists; Animals; Heart Failure; Humans
PubMed: 17266464
DOI: 10.1517/14656566.8.3.289 -
Journal of Medicinal Chemistry Oct 1981A series of gamma-methyl- (5) and alpha-methyl(aryloxy)propanolamines (6) were synthesized and evaluated for beta-adrenergic blocking action. The binding constant (KD)...
A series of gamma-methyl- (5) and alpha-methyl(aryloxy)propanolamines (6) were synthesized and evaluated for beta-adrenergic blocking action. The binding constant (KD) was determined for compounds 5a-j on cultured C6-2B astrocytoma cells. Compounds 5a-j and 6a-e were evaluated for beta 1-antagonist action on guinea pig atria and beta 2-antagonist action on guinea pig tracheal strips. Several gamma-methyl(aryloxy)propanolamines showed affinity for beta receptors and a possible preference for beta 2 receptors.
Topics: Adrenergic beta-Antagonists; Animals; Guinea Pigs; Heart; In Vitro Techniques; Propanolamines; Receptors, Adrenergic, beta; Structure-Activity Relationship; Trachea
PubMed: 6120233
DOI: 10.1021/jm00142a017 -
Acta Anaesthesiologica Scandinavica.... 1982A short review is given of the distribution of and effects mediated through beta-receptors. The pharmacodynamic profiles of some beta-receptor agonists and antagonists... (Review)
Review
A short review is given of the distribution of and effects mediated through beta-receptors. The pharmacodynamic profiles of some beta-receptor agonists and antagonists are briefly outlined and the clinical advantages and disadvantages of different pharmacodynamic properties are discussed.
Topics: Adrenergic beta-Agonists; Adrenergic beta-Antagonists; Humans
PubMed: 6152879
DOI: 10.1111/j.1399-6576.1982.tb01884.x -
Basic Research in Cardiology 2000Beta-blockers have several beneficial cardiovascular effects in patients with hypertension, angina pectoris, myocardial infarction, and congestive heart failure. In... (Review)
Review
Beta-blockers have several beneficial cardiovascular effects in patients with hypertension, angina pectoris, myocardial infarction, and congestive heart failure. In patients with myocardial infarction and congestive heart failure some beta-blockers have been found to reduce mortality and morbidity. The beta-blockers with a proven effect on prognosis include timolol, metoprolol, propranolol, bisoprolol, and carvedilol. One important question is whether all cardiovascular effects obtained by beta-blockers can be considered to be class effects. The beta-blockers with favorable effects on prognosis include two with more selective beta1-receptor blockade (metoprolol and bisoprolol) and three non-selective (timolol, propranolol and carvedilol). One non-selective beta-blocker, which also has a more pronounced class III effect, sotalol, has been studied in a large postinfarction study without a significant effect on mortality. However, sotalol reduced the incidence of reinfarction similarly to the other beta-blockers with proven effect on mortality after myocardial infarction. Sotalol had no influence at all on sudden cardiac death, while all the other beta-blockers referred to above have a very marked effect on sudden cardiac death, in fact more marked than on overall mortality. The beta-blockers with proven effect on mortality and on sudden death have one property in common and that is some degreee of lipophilicity. Sotalol and atenolol are hydrophilic. From animal experimental data it has been suggested that beta-bockers with some degree of lipophilicity penetrate into the brain and have an indirect effect on vagal activity, which is of importance for prevention of ventricular fibrillation and sudden cardiac death. It can be summarized that some beta-blockers have been found to reduce mortality and sudden cardiac death in patients after myocardial infarction and in congestive heart failure, while others have not. It seems that the major properties of the beta-blockers with proven effects on mortality and sudden cardiac death are beta1-receptor blockade and some degree of lipophilicity. Until we know more about the mechanisms behind prevention of death and especially sudden cardiac death by beta-blockers, only drugs with proven effects on prognosis should be used.
Topics: Adrenergic beta-Antagonists; Animals; Death, Sudden, Cardiac; Humans; Lipids; Solubility
PubMed: 11192352
DOI: 10.1007/s003950070008 -
Clinical Physiology and Biochemistry 1990Several beta-adrenoceptor blockers with various ancillary properties besides beta-receptor blockade are now available for clinical use. In the treatment of hypertension,... (Comparative Study)
Comparative Study Review
Several beta-adrenoceptor blockers with various ancillary properties besides beta-receptor blockade are now available for clinical use. In the treatment of hypertension, angina pectoris, and certain types of cardiac arrhythmia the therapeutic benefit is mediated by beta 1-receptor blockade, whereas the blockade of beta 2-adrenoceptors does usually not contribute to the therapeutic efficacy and is rather associated with adverse reactions. Accordingly, all properties other than beta 1-adrenoceptor blockade should be considered as ancillary properties. The following properties of beta-blockers and the therapeutic relevance of these properties are to be discussed, together with pertinent examples of the drugs involved: beta 1-receptor selectivity and the degree of beta 2-receptor blockade; intrinsic sympathomimetic activity (ISA); duration of action (to be discussed in connection with the pharmacokinetic properties in Prof. Borchard's presentation); lipophilicity, brain penetration and CNS side effects, and cardioprotective properties (secondary prevention following myocardial infarction). Most of these properties have been investigated in full detail and a wide variety of compounds possessing one or more of these properties have been introduced. With respect to the future, beta 1-adrenoceptor selectivity remains an interesting issue, although it is difficult to imagine that compounds which are even more beta 1-selective than bisoprolol can be developed. The cardioprotective activity of beta-blockers deserves further investigations, in particular with respect to the underlying mechanisms. Finally, many new beta-blockers are now becoming available with an additional vasodilator component which may be caused by different mechanisms, like 'direct' vasodilation, beta 2-receptor agonism, alpha-adrenoceptor blockade, or angiotensin-converting enzyme inhibition. The various mechanisms and possible clinical relevance will be discussed.
Topics: Adrenergic beta-Antagonists; Anesthesia; Cardiovascular Diseases; Cell Membrane; Humans; Receptors, Adrenergic, beta
PubMed: 1982758
DOI: No ID Found