Related Experiment Video
Updated: Sep 20, 2026

Quantifying Agonist Activity at G Protein-coupled Receptors
Published on: December 26, 2011
Single-isomer beta-agonists
1Sepracor, Inc., Marlborough, Massachusetts 01752, USA.
Abstract:
A new generation of bronchodilators is being developed for acute asthma management-single-isomer beta-agonists. These drugs consist only of the active bronchodilatory isomer (eutomer); they do not have the inactive and potentially harmful isomer (distomer) that is present in marketed racemic beta-agonists. Clinical studies comparing the effectiveness of (R)-albuterol (levalbuterol) with racemic albuterol established a strong rationale for using single-isomer beta-agonists in place of the racemic mixture: reduced dosages provide equivalent bronchodilatory effects with fewer beta-mediated side effects. Higher dosages achieve superior bronchodilation in episodes of severe asthma and may reduce costs of emergency department treatment.
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