They both give you gas but Metalmucil more because of the sugar I am told. What you need to do is lower the dosage and increase it slowly, giving your body 3 weeks to get used to the increased fibre (the body develops the bacteria to deal with it, etc). Also, drink plenty of water (because you will have a problem if you don't). It helped me a lot.
[This message has been edited by moderator4 (edited 04-06-2003).]