Brian, The March 1998 issue of U.S. Pharmacist has a 16 page insert by Roche Laboratories,340 King St,Nutley,NJ 07110-1199 entitled "New Therapeutic Options for Parkinson's Disease"written by Darrel J.Hulisz,Pharm.D.. It is stated there that the "maximum effective dosage" of carbidopa is 100-125mg/day. In your Living with Levadopa paper,Section 3.5,you give a "safe upper limit" of 300mg/day. Is there any contradiction here with regard to the effectiveness of raising Sinemet dosages? Gil Lieberman,CG for Aliza,PD,74/3+