[Bowel gases].

Abdominal bloating is one of the most common symptoms in patients with different gastrointestinal disorders. The majority of patients usually attribute this complaint to increased intestinal gas volume. Recent experimental studies using the gas challenge test help us to better understand the gas dynamics and tolerance in humans. Although there are some clinical conditions that are clearly related to impaired gas dynamics, the role of gases in functional gastrointestinal disorders especially in irritable bowel syndrome is much more complicated. Impaired gas handling, abnormal reflexes and visceral hypersensitivity seem to be the main factors resulting in abdominal bloating in this group of patients. Further clinical studies are needed to clarify the pathophysiologic mechanisms of intestinal gas and this may contribute to the evaluation of optimal therapy.