The Pharmacologic Treatment of Alzheimer's Disease: A Guide for the General Psychiatrist

Abstract

Objective: To review the drug treatment of Alzheimer's disease (AD) and to provide guidelines for the physician on how to integrate these treatments into the overall management of this disorder. Method: A qualitative review of randomized, double-blind, placebo-controlled trials of medications used to treat cognitive deficits, disease progression, agitation, psychosis, or depression in AD. A computerized search of Medline was used to identify relevant literature published during the period 1968–1998. Key words used in the search were 'randomized controlled trials, ' with 'dementia' and with 'Alzheimer's disease'. Results: Agents that are currently available in Canada to treat the cognitive deficits of AD include donepezil, ginkgo biloba, selegiline, and ergoloid mesylates. Donepezil and ginkgo biloba are associated with a statistically significant but clinically modest improvement in cognitive function in a substantial minority of patients with mild to moderate AD. Selegiline may have a mild beneficial effect on cognitive function in some patients with AD, but the data are inconclusive. Ergoloid mesylates have questionable efficacy in AD and can only be recommended as a last line of treatment. The results of a single trial suggest that vitamin E or selegiline (both have antioxidant properties) may slow the progression of AD. Antipsychotic medications can result in clinically significant improvement in agitation and psychosis. Carbamazepine also appears to be an effective treatment for agitation in AD, and there is preliminary evidence that the selective serotonin reuptake inhibitor Citalopram reduces irritability in this disorder. There is no evidence that other nonneuroleptic medications are more efficacious than placebo in treating agitation in AD. Limited data indicate that depression in dementia responds to antidepressant medication. Conclusion: These data indicate that selected medications can be used to treat cognitive deficits, disease progression, agitation, psychosis, and depression in AD. However, there is considerable heterogeneity in patients' responses to these medications. Pharmacotherapy needs to be considered as a component of a package of care that also includes psychosocial and environmental interventions and support of the caregiver.