Computerized drug utilization review (DUR) can potentially reduce adverse drug events. We examined automated DUR for home healthcare patients with diabetes or hypertension. Sixty-eight percent of diabetes patients and 50.7% of hypertension patients triggered severe, moderate, or duplicative alerts. Among diabetes patients, 74.3% of duplicative alerts were trivial or inappropriate, compared with 3.9% among hypertension patients. Experts judged that 40.5% of high-risk diabetes patients and 53.6% of hypertension patients had alerts requiring nurse follow-up. Adequate follow-up was significantly lower for the former. The relationship between inappropriate alerts and poorer follow-up reinforces the need for more specific alert systems to focus clinicians' attention on clinically important alerts.