In addition to trying to take as much daily fiber as I can, the psyllium is the most effective for me. I started taking it about 35 years ago and have chosed to take Konsyl (no sugar) rather than Metacil which most people seem to take. One dose is 6 mg. while Metacil has 3.5 mg. I take it twice/day now rather than once/day and take it with fruit juice which makes it sweet and pallitable (sp.?). It must be mixed very thoroughly and taken right away. It should not be taken at the same time as the Parkinson meds as it might interfere with the efficacy of the P/D pills. Sometimes I forget the 2nd dose because I am so tired and I notice the ill effect the next day. Before I started taking meds for P/D, this was all I took and it was very effective. Now that I am diagnosed P/D, I have an inert colen and have to work hard to keep things moving.