Comments on the article by M. Farlow et al (see record 2000-12450-003) which evaluated the efficacy of rivastigmine in Alzheimer's patients. The current author states that although Farlow et al's long term efficacy results look promising, this open label extension needs confirmation from double blind placebo controlled studies. Unless clinical trials can demonstrate improvement in quality of life and delay in progress to severe dependency or institutionalization, the role of rivastigmine, and perhaps cholinesterase inhibitors in general, remains controversial and hence does not justify its widespread use in AD.