The use of intermittent subcutaneous injections of oxycodone for opioid rotation in patients with cancer pain

Oxycodone is a strong opioid that has been available for at least 70 years. At present, commercially prepared parenteral oxycodone is only available in Finland. We report in this paper our experience of administering oxycodone s.c. From 21 October 1996 to 31 July 1998, 63 advanced cancer patients received intermittent s.c. injections of oxycodone via the Edmonton Injector, a simple, low-cost mechanical device. Local tolerance and systemic toxicity were followed prospectively. Only 2 patients developed s.c. injection site intolerance, and in both cases doses of 50 mg/ml or more were being administered. Most of the patients in this study were rotated to oxycodone because of opioid toxicity, and in 34% of those patients their delirium subsided. A subgroup of 19 patients who underwent rotation to oxycodone SC from morphine and hydromorphone were studied for equivalent analgesia with oxycodone. We found a ratio (mean ± SD) of 1.2 ± 0.4 for morphine s.c. to oxycodone s.c. and a mean ratio of 0.5 ± 0.4 for hydromorphone s.c. to oxycodone s.c. When hydromorphone s.c. was converted to a morphine s.c. equivalent dose and the results for these patients were added to those for the morphine s.c. group, the mean and median overall ratios of morphine s.c. equivalent dose to oxycodone were 1.9 ± 1.5 and 1.4, respectively. The cost of the oxycodone s.c. was also evaluated and was found to be comparable to that of morphine s.c. and lower than that of hydromorphone s.c. We conclude that s.c. oxycodone can be an effective, safe and inexpensive alternative opioid agonist.