Clinical use of beta-adrenergic agonists.

In the last decade the treatment of airway obstruction has been greatly facilitated by the introduction of a number of long-acting, highly bronchoselective beta-adrenergic agonists. Many medical professionals feel that these agents should be first-line treatment for asthma. The choice of route of administration and drug to use depends on the desired clinical effect. Most studies in both acute and chronic situations demonstrate that the inhaled route produces at least as much bronchodilation as oral or parenteral therapy and does so with substantially fewer side effects. Fears about safety and tachyphylaxis with the modern agents have been unfounded. Failure of self-administered beta-agonists to produce relief from acute episodes of airway obstruction cannot be interpreted as evidence of primary drug resistance and does not predict the emergency room response to these agents. The available evidence suggests that if drug tolerance does develop with beta-agonists, it is small in magnitude, nonprogressive, and not clinically significant.