Enhancement of memory processes in Alzheimer's disease with multiple-dose intravenous physostigmine.

Physostigmine (.125 mg, .25 mg, or .50 mg) or placebo was administered intravenously to 10 neuroleptic-free patients with Alzheimer's disease over a 30-minute period. All patients performed better on a recognition memory task while receiving physostigmine. When placebo or the dose of physostigmine previously associated with an improvement in memory was readministered, physostigmine again enhanced performance on a recognition memory task. These results indicate that the acute augmentation of cholinergic activity in some patients with Alzheimer's disease can partially reverse the memory deficit of that disorder and may provide an approach to the eventual therapy of this condition.