Cholinesterase inhibitors in the treatment of dementia.

Dementia associated with probable Alzheimer's disease (AD) is one of the most common types of dementia. Patients with AD often have cholinergic deficits in association with the disease. The cholinesterase inhibitors donepezil hydrochloride, galantamine hydrobromide, and rivastigmine tartrate are the current mainstays of symptomatic treatment for patients with AD. In clinical trials for all three agents, beneficial effects on standard measures of cognitive and global function have been observed in patients with mild to moderate AD. Although none of the cholinesterase inhibitors has been approved for treatment of patients in advanced stages of AD, all three agents have had beneficial cognitive effects among patients with less severe forms of the disease. The author provides information on recommended dosing for all three medications, noting that cholinesterase inhibitors must be titrated carefully. When administered with caution, galantamine, rivastigmine, and donepezil are generally well-tolerated pharmacologic treatment options. The author notes that, after patients and their caregivers understand that no change in status is considered an "improvement" and a desirable clinical outcome for patients with AD, if no benefits are achieved with the use of one cholinesterase inhibitor, switching to another medication in this class might be beneficial. The author further suggests that the benefits found in cholinesterase inhibitors for patients with AD might also be applicable to patients with other types of dementia such as vascular dementia and dementia with Lewy bodies as cholinergic deficits have been reported in association with these types of dementia as well.