Dextofisopam, a non-serotonergic agent currently being evaluated for the treatment of irritable bowel syndrome (IBS), is the R-enantiomer of racemic tofisopam, a molecule marketed and used safely outside the United States for over three decades for multiple indications including IBS. Dextofisopam represents a novel, first-in-class opportunity with a positive proof-of-concept study in an arena where there are few compounds with unique approaches or positive efficacy results. By structure, Dextofisopam is a member of the homophthalazine class; Dextofisopam binds to specific receptors in areas of the brain affecting autonomic function, including gastrointestinal (GI) function. Unlike the two 5-HT3 or 5-HT4 mediated IBS therapies currently available, both with significant safety concerns, Dextofisopam novel non-serotonergic activity offers a unique and innovative approach to IBS treatment. Recent studies have indicated that dextofisopam binds to a novel binding site within the central nervous system that may be responsible for mediating its actions. This receptor has been characterized as the 2,3-benzodiazepine receptor, which is distinct from the classical 1,4 or 1,5-benzodiazepine receptor. Dextofisopam has no significant binding at other receptors or ion channels