Recent research has shown that while Lewy body dementia. (LBD) may be the second most common form of dementia, it is difficult to confirm the disease before autopsy. Patients with LBD share many clinical signs and symptoms with patients diagnosed with Alzheimer's disease (AD), making it difficult to differentiate between the two diseases in patients who are still living. Still, our purpose in this study was to determine any clinical features which may differentiate between autopsy-confirmed cases of AD and cases of LBD. We compared 13 patients with autopsy-confirmed AD with 12 patients who had autopsy-confirmed LBD. Phone calls were made to family members of the deceased to help clarify and add any other information not documented in the patient's files. Significant differences were found in three areas, and trends approaching statistical significance were found in two other areas. Visual hallucinations were more prominent in the patients with LBD than in the patients with AD (10/12 LBD vs. 4/13 AD, P < 0.05). A nonspecific tremor was also found more often in the LB patients than in the Alzheimer's patients (8/12 LBD vs. 3/13 AD, P < 0.05). Finally, the LB patients were more prone to wandering, especially earlier in the disease course than were the patients with AD (10/12 LBD vs. 6/13 AD, P < 0.5). There was also a trend within the LB patients for higher use of anxiolytics (9/12 LBD vs. 6/13 AD, P = 0.14) as well as antidepressants (7/12 LBD vs. 4/13 AD, P = 0.16). Our data confirmed our hypothesis that LBD from a clinical perspective is indeed similar to AD. However, the higher incidence of visual hallucinations, tremor and wandering as well as the trend toward the use of anxiolytics and antidepressants among LB patients was noted. This gives hope that a clinical differentiation between these two diseases and more specific treatments may be possible in the future.