Optimization of beta-blockers' pharmacology.
Beta-adrenergic-blocking drugs (BABs) have a firm place in the therapy of cardiovascular conditions including angina and hypertension. Although all BABs are competitive inhibitors of beta-receptors, they may differ in their additional pharmacodynamics, i.e., beta1-(cardio)selectivity, partial agonistic activity (PAA), and pharmacokinetic properties. Understanding these additional properties would allow the physician to choose the more appropriate agent for some patients or for specific situations. beta1-Selective BABs may be of potential importance in patients with obstructive airway disease, peripheral vascular disease, and hyperlipidemia and in diabetic patients receiving antidiabetic drugs. These BABs may better control the increased blood pressure in response to hypoglycemia, exercise, or cigarette smoking. Nonselective BABs may be preferably used to decrease epinephrine-induced hypokalemia or to prevent myocardial infarction, and in certain circumstances (i.e., migraine, anxiety, thyrotoxicosis or essential tremor). BABs with PAA may theoretically cause a lesser degree of cardiodepression (reduction of heart rate at rest, cardiac output, and AV conduction), bronchospasm, and peripheral vasoconstriction and minor effects on plasma lipids. Withdrawal syndrome may be absent after BABs with PAA. The pharmacokinetic properties of the BABs such as absorption, bioavailability, elimination half-life, liver metabolization, interindividual variability, as well as pharmacological interactions depend on their hydrophilic/lipophilic ratio. The development of new BABs continues. It has been possible to incorporate into a drug molecule combinations of PAA, preferred beta1-blockade, and beta2-agonist activity. Even if these new agents cause less adverse effects (e.g., vasoconstriction, bronchospasm), their clinical significance remains to be established.
Tamargo
J
J
Institute of Pharmacology and Toxicology, School of Medicine, Universidad Complutense, Madrid, Spain.
Delpón
E
E
D000319:Adrenergic beta-Antagonists / Q000145:classification / Q000494:pharmacology* / Q000627:therapeutic use; D000818:Animals; D006331:Heart Diseases / Q000188:drug therapy / Q000378:metabolism; D006801:Humans; D018342:Receptors, Adrenergic, beta-1 / Q000378:metabolism*; D018343:Receptors, Adrenergic, beta-2 / Q000378:metabolism*; D012120:Respiration Disorders / Q000188:drug therapy / Q000378:metabolism
D000319:Adrenergic beta-Antagonists; D018342:Receptors, Adrenergic, beta-1; D018343:Receptors, Adrenergic, beta-2