The most common symptoms associated with intestinal gas are excessive eructation, flatulence, and abdominal bloating and distention. Unfortunately, few therapies have been shown to be effective in treating these symptoms. Excessive eructation can be treated by decreasing excessive air swallowing. Bloating and gaseous distension can improve in some patients by avoiding foods containing partially digested or absorbed polysaccharides, by taking replacement enzymes (such as alfa-galactosidase or lactase), or by taking antibiotics directed toward altering the colonic flora. Activated charcoal or prokinetic agents (such as tegaserod and metoclopramide) also can be effective options in some patients. For noxious odor associated with flatus, bismuth subsalicylate or the charcoal cushion may improve patients' symptoms.