It is not unusual-- Metamucil contains Psyllium which is a natrual fiber that absorbs alot of water and expands rapidly, it digests, ferments and forms gas. Some people are more sensitive than others-- many of us react differently. My wife takes it in a capsual form so it get to the intestines before working.
When starting to use it, you should start off at a low dose if using the powder form then increase it as your system gets use to it--- and usually the GAS goes away.
I know exactly what you're talking about. I have a cancerous tumor in my colon that makes things harder to move through and subsequently there is constipation. I took metamucil last night and had planned to continue until my surgery (Aug 5th). I felt as if I was 5 months pregnant by the time I went to bed and the bloated feeling was just unbearable. I drank some warm ginger tea (i get it in the ethnic section of my supermarket) and it helped the gas to pass through. I still had some gas this morning when I woke up. I think I'll not take anymore of this. The constipation is better.
It gave me gas too. I find that oatmeal for breakfast does exactly what the metamucil is taken for without gass and bloating. It just takes longer to boil oatmeal than it to throw down metamucil. Try it, oatmeal doesn't cost much(isn't covered by any drug plan though )