Donepezil as add-on treatment of psychotic symptoms in patients with dementia of the Alzheimer's type

Traditionally, the neuropsychiatric symptoms of Alzheimer's disease (AD) have been managed with neuroleptics or benzodiazepines, which have serious side effects. Preliminary observations suggest the possible value of cholinesterase inhibitors in the amelioration of psychotic symptoms in patients with dementia of the Alzheimer's type, dementia with Lewy bodies, and in patients with Parkinson's disease. Twelve inpatients with AD with psychotic symptoms and lack of improvement of their delusions/hallucinations during perphenazine treatment (8 mg/day) for 3 weeks received random open-label donepezil 5 mg daily in addition to an ongoing treatment of 8 mg/day perphenazine or 16 mg/day perphenazine. Assessments conducted at baseline and after weeks 2 and 4 included the Mini-Mental State Examination, the Global Deterioration Scale, the Positive and Negative Symptoms Scale, and the Clinical Global Impressions scale. Frequency of extrapyramidal symptoms was measured according to the Abnormal Involuntary Movement Scale. The donepezil-perphenazine group exhibited substantially greater and clinical improvements in mental state. At the end of the trial (4 weeks), Positive and Negative Symptoms Scale scores revealed significant differences between both groups (p = 0.006). The Clinical Global Impressions scale and the Mini-Mental State Examination scores also showed significant differences between the donepezil-perphenazine group and the perphenazine group (p = 0.028 and p = 0.027 respectively). No significant differences were found in the Global Deterioration Scale scores. Abnormal Involuntary Movement Scale scores showed a significant deterioration in extrapyramidal symptoms in the perphenazine group compared with the donepezil-perphenazine group (p = 0.016). Donepezil augmentation of neuroleptics may be appropriate for those patients for whom neuroleptic monotherapy either does not lead to symptom remission or is associated with intolerable adverse effects. This was an open-label study and there is need for larger studies with double-blind control and a long-term study design to define the efficacy of donepezil for patients with AD and psychotic symptoms.