Donepezil: new preparation. Moderate efficacy in Alzheimer's disease.

(1) Donepezil is an anticholinesterase indicated for the symptomatic treatment of Alzheimer's disease. (2) Three comparative placebo-controlled trials are available, and show that the effects of donepezil are moderate and visible only on psychometric scales; the possible clinical benefit is unknown. In the long term, donepezil only delays cognitive deterioration by a few months. (3) No published trials have yet compared donepezil with tacrine. (4) During clinical trials and the first months on the US market the adverse effect profile of donepezil was acceptable. No hepatotoxicity has yet been described, although it is known to occur with tacrine.