There is evidence from the clinical and experimental literature that the elderly may be more susceptible to the anticholinergic side effects associated with antidepressant drugs. Fifty-four elderly depressed subjects participated: 27 were taking antidepressants and 27 were unmedicated controls matched for severity of depression, age, and education. The medicated subjects showed a mild, but statistically significant, deficit on a set of six measures of memory performance. However, it was unclear whether this deficit was related to anticholinergic activity. It appears that, while antidepressant medications may not be benign in terms of memory functioning in the elderly, the memory difficulties are mild and are not similar to those of Alzheimer's patients. Thus, differential diagnosis of depression and dementia should not be greatly complicated by antidepressant medication.