Camilla; Good luck with the Aricept. Ken has been on 5mg.per day for three weeks now, and we are all noticing improvement each day. I hope you and Peter have the same experience. One interesting and helpful side effect for us is that Ken is having a bowel movement almost every day and with much less stool softening or laxative help. From our point of view, this is a much appreciated side effect. Our Neuro said that Ken's dementia is atypical of both AD and PD, so it could be from a shortage of acetylcholine. It seems that she may be right. We increase to 10mg in a couple of weeks if all goes well, and I will keep you posted. In addition to sinemet, Ken takes florinef, midodrine, zoloft, and NADH, so there is alot of drug interaction potential, but we have noticed nothing. Good luck to you both Barbara Smith, CG/Ken,69, PD/16yrs.SDS/5 yrs.