Pharmacological approach to chronic visceral pain. Focus on oxycodone controlled release: an open multicentric study.

BACKGROUND AND OBJECTIVES Visceral pain is a significant issue for patients, and the importance of treating pain is underestimated. New opioid formulations, the primary treatment option for moderate-to-severe pain, have been shown to be effective, but no studies have been conducted to address the efficacy of these agents for visceral pain. This study was conducted to determine the incidence of visceral pain in patients with uncontrolled moderate-to-severe pain, and to evaluate the efficacy of controlled-release (CR) oxycodone in this context. MATERIALS AND METHODS s: In this multicenter, prospective, observational study, 967 of 980 evaluated patients were included, 350 (36.2%) of whom presented mainly visceral pain. In most cases (57.0%), patients had experienced pain for < or = 3 months, and the majority (94.9%) were cancer patients. Pain was uncontrolled in 340 (97.1%) patients, and was rated as severe in >2/3 of patients (mean numerical rating scale (NRS) value 7.04 +/- 1.68). Patients with uncontrolled pain were given oxycodone CR; all completed the 15-day study and no patient was switched to an alternative opioid. RESULTS Oxycodone CR was associated with significant reductions in mean NRS value at day 3, 7 and 15 (final mean NRS 2.37 +/- 1.59) and the proportion of patients experiencing severe pain had decreased by the end of the study to 1.5%. The SF-12 questionnaire showed significant improvements in quality of life in all domains, and oxycodone CR was well tolerated. CONCLUSIONS Oxycodone CR appears to be a very well tolerated and effective treatment for patients with visceral pain.