ibuterol

Ibuterol is a small molecule prodrug of the selective beta-2 adrenergic agonist terbutaline. Chemically, it is the di-isobutyric acid ester of terbutaline. Developed by Draco (a subsidiary of Astra, now AstraZeneca), ibuterol was designed to improve the oral bioavailability and duration of action of terbutaline for the treatment of asthma and other obstructive airway diseases. Following oral administration, ibuterol is hydrolyzed by esterases in the body to release the active moiety, terbutaline. Terbutaline then stimulates beta-2 adrenoceptors in the bronchial smooth muscle, leading to bronchodilation. Clinical studies in the 1970s demonstrated that ibuterol is more potent than terbutaline on a milligram-for-milligram basis when administered orally, though it is no longer widely marketed in major pharmaceutical markets.

Brand names

Spiranyl

Other names

ibuterol hydrochloridediisobutyrylterbutalinediisobutyryl terbutaline