Cepeda MS, et al.: Side effects of opioids during short-term administration : Effect of age, gender, and race. Clin Pharmacol Ther, 74 (2) : 102-112, 2003
Okamoto Y, et al.: A retrospective chart review of the antiemetic effectiveness of risperidone in refractory opioid-induced nausea and vomiting in advanced cancer patients. J Pain Symptom Manage, 34:217-222, 2007