We compared three groups of older psychiatric outpatients on numbers and types of physical illnesses and on number of nonpsychotropic medications. The subjects included 62 patients with Alzheimer's disease (AD), 41 with major depression (MD), and 78 with schizophrenia (SZ). The mean age in this predominantly male population was 68.4 years. Psychiatric diagnoses were based on DSM-III-R criteria. We utilized intake psychiatric assessments, chart reviews, and computerized pharmacy profiles to collect the data. The patients with SZ had significantly lower comorbidity compared to patients with MD, and had a significantly lower number of nonpsychotropic medications prescribed than both the AD and MD groups. These findings may reflect biological differences or may be secondary to differences in psychiatric treatment or in the use of health care resources. Alternatively, the low prevalence of physical comorbidity in SZ may represent a survivor or healthier cohort of patients.