Evolving concepts in irritable bowel syndrome

Converging evidence from investigations of the peripheral and central aspec ts of bidirectional brain-gut interactions is beginning to shape a pathophy siological model of irritable bowel syndrome (IBS) and related functional g astrointestinal (GI) disorders. This neurobiological model includes alterat ions in autonomic, neuroendocrine, and pain modulatory mechanisms. The freq uent association of IBS and other functional GI disorders with co-morbid af fective disorders and temporal association of symptom exacerbation with psy chosocial or physical stressors are consistent with alterations in the neur obiological mechanisms underlying the central stress response. Renewed inte rest in drug development for IBS has resulted in development of instruments for the better assessment of the impact of global symptoms on quality of l ife and in the development of candidate compounds undergoing clinical evalu ation.