Paradoxical response to levalbuterol.

Asthma is a common condition that can substantially affect patients' quality of life. Although several drugs, most commonly beta-adrenergic agonists, alleviate symptoms of asthma, they may cause paradoxical bronchospasm or paradoxical bronchoconstriction. Levalbuterol hydrochloride-a pure form of the (R)-stereoisomer in racemic albuterol-eliminates the adrenergic properties that can cause such adverse effects. However, we report a case of paradoxical bronchoconstriction in a 36-year-old man who was recently diagnosed as having new-onset asthma and was treated with levalbuterol.