Beta adrenergic agonists

Beta adrenergic agonists are the most widely used agents in the management of bronchospasm as a result of their rapid onset of action and predictable efficacy. Administration of these agents by inhalation provides several advantages, including rapid effect, decreased adverse effects, and fewer drug interactions. The newer agents have greater beta-2 selectivity, which contributes to improved tolerance of these agents. Tremor is usually the dose-limiting side effect for the beta-2 selective agents. Other adverse effects include tachycardia, increased blood pressure, headache, anxiety, abnormal glucose metabolism, and hypokalemia. Controversy surrounding the use of beta adrenergic agonists includes reports of an increased mortality rate with increased use of these agents. Current information is inconclusive and should not limit the use of these agents in the management of acute bronchospasm. The significance of tolerance with prolonged administration is also an unresolved issue.