Fybogel Fibre Chews Citrus Flavour (60). Fybogel Fiber Chews gently relieve constipation and help to maintain regularity. Fibre Chews works naturally with the body and use the ingredient.. Fibersol -2 (a type of fibre) to help get you back to regularity. It works by retaining water in the stool, and may also help to bulk-up stools, making them easier to pass.. Adults and children over 12 years of age