Donepezil: tolerability and safety in Alzheimer's disease

The tolerability and safety of donepezil HCI in patients with mild to moderate Alzheimer's disease (AD) were examined in an integrated analysis of phase II/III placebo-controlled trials. Patients with mild to moderately severe AD (n=1,920) were randomised to receive donepezil (n=1,291) or placebo (n=629). Adverse events, physical examinations and clinical laboratory tests were assessed. A high completion rate (79%) was achieved in these trials. Of the 1,291 patients receiving donepezil only, 142 (11%) withdrew because of an adverse event compared with 43 of the 629 (7%) placebo patients. The most common adverse events included nausea, diarrhoea, headache, insomnia, dizziness, rhinitis, vomiting, asthenia/fatigue and anorexia. Donepezil had no clinically significant effect on any laboratory evaluations and was not associated with hepatotoxicity. These results demonstrate that donepezil is well tolerated and has a favourable safety profile at clinically effective, once-daily doses of 5 mg and 10 mg.