Concerns that high dose opioids and sedatives might shorten patient survival could contribute to insufficient symptom alleviation for terminally ill cancer patients. To examine the effects of opioids and sedatives prescribed in the final 48 hours on patient survival, a re-analysis of the prospectively collected data was performed on 209 hospice inpatients. Patient characteristics and clinical symptoms were prospectively recorded, and information about the use of opioids and sedatives in the last two days was collected by a chart review. Opioids were prescribed in 82% of the patients, with a median dose of 80 mg oral morphine equivalent (OME)/48 hours. Sixty percent received some sedative medications, mainly haloperidol (43% of total sample, 7.5 mg/48 hours), midazolam (23%, 23mg/48 hours), and hydroxyzine (15%, 50 mg/48 hours). There were no significant differences in survival between the patients who received different doses of opioids (<240, 240--599, and > or =600 mg OME/48 hours) and of benzodiazepines (0, 1--59, and > or =60 mg parental midazolam equivalent/48 hours). Also, the survival of patients with haloperidol, hydroxyzine, and other sedative medications did not differ from those without. Furthermore, an addition of use of opioids and sedatives in the final 48 hours into the multiple regression model for survival prediction achieved no significant increase in predictability. In conclusion, opioids and sedatives used for symptom control in the last days are not associated with patient survival. They are safe and useful medications to palliate severe distress in the terminal stage of cancer when administered with a low initial dosage and adequate titration.