Citrucel Powder Orange Flavor Relieves constipation (irregularity). Helps to restore and maintain regularity. For constipation associated with other bowel disorders like IBS when recommended by a doctor. Generally produces a bowel movement in 12-72 hours. Citrucels unique smartfiber is smart because it is: The only fiber for regularity that won't ferment to cause excess gas like other fiber products. Gentle and effective to help restore and maintain regularity. 100% soluble non-allergenic and gluten-free. Based on laboratory testing. Individual results may vary.