Oxycodone/naloxone in the management of patients with pain and opioid-induced bowel dysfunction.

INTRODUCTION: Common opioids adverse effects include opioid-induced bowel dysfunction (OIBD), which comprises opioid-induced constipation, dry mouth, nausea, vomiting, gastric stasis, bloating, and abdominal pain. Traditional laxatives which are often prescribed for the prevention and treatment of OIBD possess limited efficacy and display adverse effects. A targeted approach to OIBD management is the use of a combination of an opioid agonist with opioid receptor antagonist or administration of purely peripherally acting opioid receptor antagonists.

METHODS: A literature search with terms "oxycodone/naloxone" in the PubMed and MEDLINE database updated on 31(st) July 2013. All studies of oxycodone/naloxone (randomized, controlled trials and open, uncontrolled studies) were included. In addition, studies on pharmacokinetics and pharmacodynamics of oxycodone/naloxone were included.

RESULTS: A combination of prolonged-release oxycodone with prolonged-release naloxone (OXN) in one tablet with a fixed 2:1 ratio provides effective analgesia with limited disturbing effect on bowel function. Oxycodone is a valued opioid administered either as the first strong opioid or when other strong opioids have been ineffective. Naloxone is an opioid receptor antagonist that displays local antagonist effect on opioid receptors in the gastrointestinal tract and is nearly completely inactivated in the liver after oral administration. As demonstrated in controlled studies conducted in patients with chronic non-malignant and cancer-related pain OXN in daily doses up to 80 mg/40 mg provided equally effective analgesia with an improved bowel function compared to oxycodone administered alone.

CONCLUSION: OXN is an important drug for chronic pain management, prevention and treatment of OIBD.