The authors compared the efficacy and side effects of trazodone and haloperidol for treating agitated behaviors associated with dementia. Twenty-eight elderly patients with dementia and agitated behaviors were randomly assigned to double-blind treatment with either trazodone (50-250 mg/day) or haloperidol (1-5 mg/day) for 9 weeks. There was no significant difference in improvement between the medication groups. Adverse effects, however, were more common in the group treated with haloperidol. Improvement in individual areas suggested that repetitive, verbally aggressive, and oppositional behaviors responded preferentially to trazodone, whereas symptoms of excessive motor activity and unwarranted accusations responded preferentially to haloperidol. These results indicate that moderate doses of trazodone and haloperidol are equally effective for treatment of overall agitated behaviors in patients with dementia, but specific symptoms may respond preferentially to a particular agent.