Ah! I think I found what your doc was talking about...
This alzheimer like syndrome he mentioned, did he say anything that sounded like PML or progressive multifocal encephalopathy? That is the only warning that's out at the moment with regards to cellcept from what I can see. A very very small number of patients on cellcept got PML and Roche (the company that makes cellcept) notified the FDA (as it is supposed to in the case of new side-effects however rare) about the isolated cases and issued notification letters to health professionals on May 29th 2008.
The relevant link to the FDA page is:
http://www.fda.gov/Cder/drug/early_comm/mycophenolate.htm
Unfortunately with meds we are often called to weigh the advantages versus the disadvantages and the potential benefits versus the potential harms they may cause us. Prednisone, for example, is one of those meds we love to hate and although it can save lives and reverse major flares with the speed of lightning; it can also cause osteoporosis, weight gain, skin thinning, raise blood sugar and a myriad more side-effects that are potentially harmful.
Cytoxan and rituxan, both potentially life-saving meds in very difficult situations can cause hair thinning, increased chances of infection, lowered immune response to infection, slightly increased chances of cancer; the list goes on and on and on. Admittedly it does sound terribly frightening at first; however if one thinks about it a little bit the realization that we make choices like that every single day comes pretty fast. Aspirin, ibuprofen, red meat, milk, mobic, most things around us really have potentially scary "side-effects" (potentially being the key word here!).... Granted, PML sounds scary and docs don't usually warn patients about the incredibly few deaths caused by internal bleeding in patients taking aspirin or other such meds so when they do warn us about something it's petrifying... Do remember though that drug manufacturers are required to list ALL side-effects, however rare (even if only two people in 10 million have had them) by law, hence the incredibly long side-effect lists in every bottle of motrin out there...
I hope what I wrote didn't scare you any more or make things any worse, it's just that the way I see it most things around us have pluses and minuses; the point being to carefully think about them and make an informed decision as to what is best in your case. Yes, PML sounds scary but then again so do lupus-related kidney problems. The risk of anyone getting PML from cellcept is fractional whilst the risk of you getting worse if you stop cellcept may be more than fractional etc.
Of course, the best thing to do here might be to go back to your doc with your concerns as he will be able to talk you through what has happened with cellcept and pml and to discuss any concerns you may have because of this.
Hope you get to the bottom of this soon!
Zoi