The etiology of Alzheimer's dementia (AD) is unknown, but several neurotransmitters, e.g., acetylcholine, have been implicated. Recently, the group of calcium channel antagonists have been reviewed for their potential neuropsychiatric applications. These agents are capable of enhancing cholinergic tone, neurofilament/microtubular stabilization, and regional perfusion rates. The following is a report of a randomized, double-blind, placebo-controlled, multicenter study of 227 AD patients treated with nimodipine, a 1.4 dihydropyridine derivative and calcium channel antagonist. The subgroup receiving active drug (30 mg t.i.d.) experienced a prophylactic benefit across eight measures over 12 treatment weeks when contrasted with the disease progression seen among placebo recipients. Calcium channel blockers as neurotransmitter modulators and/or via calcium's theoretical role in neurofibrillary tangles, proteolysis, or neurofilament formation may represent a therapeutic opportunity for the AD patient.