(tert-butyl)[beta-hydroxy-3,4-bis(p-toluoyloxy)phenethyl]ammonium methanesulphonate

Bitolterol is a prodrug that releases colterol on activation by esterases in the lung. Colterol is a direct-acting agonist, and the N-t-butyl group makes it β2-selective with a binding potency equivalent to that of isoetharine and terbutaline. The ester form is lipophilic, which helps to keep it local in the lung and resistant to COMT, which tends to increase its duration of action. Onset begins 2 to 4 minutes after administration, and the effect can last as long as 8 hours. It has a adverse effect profile similar to that of other β2-selective agonists, with less drowsiness and restlessness compared to other direct-acting agonists.

β2-adrenergic receptor agonist

ChEBI: The methanesulfonate salt of bitolterol. A beta2-adrenergic receptor agonist, it is used for relief of bronchospasm in conditions such as asthma, chronic bronchitis and emphysema.

Tornalate (Sanofi Aventis).