Abstract Background: Dementia with Lewy bodies (DLB) is a common dementia of the elderly. A significant cholinergic deficit has been demonstrated that may be responsive to treatment by cholinesterase inhibitors (ChEIs). Methods: A 24-week, open-label study was designed to assess the efficacy and safety of a ChEI, galantamine, in 50 patients with DLB. Results: This study showed beneficial effects with galantamine in 2 of the 3 primary efficacy parameters. The scores on the Neuropsychiatric Inventory (NPI-12) improved by 8.24 points from baseline (p = 0.01) especially in visual hallucinations and nighttime behaviors (p = 0.004). The scores on the Clinician's Global Impression of Change improved by 0.5 points from baseline (p = 0.01). The third primary efficacy parameter, the Cognitive Drug R...