isoetarine

Isoetharine is a direct-acting sympathomimetic with relatively low selectivity with β2-adrenoreceptors. However, it quickly calms bronchospasms better than more selective bronchodilators.

Bronchodilator.

Isoetharine was the first 2-selectivedrug widely used for the treatment of airway obstruction.However, its degree of selectivity and activity for 2-receptors may not approach that of some of the other agentssuch as terbutaline, albuterol, or even ISO. Because of thepresence of the β2-directing β-ethyl group and -directingisopropyl group, isoetharine is a β2-agonist and is resistantto MAO. However, because it contains the catechol ringsystem, it is metabolized by COMT and O-sulfated quiteeffectively. Consequently, it has a short DOA similar to thatof ISO and is used only by inhalation for the treatment ofacute episodes of bronchoconstriction.