Evaluation of topical morphine for treatment of oral mucositis in cancer patients.

introductionOral mucositis is a painful side effect to chemotherapy. Orally applied opioids may offer analgesia with fewer side effects than systemic opioids.

methodsA randomized trial comparing the analgesic effect of a morphine oromucosal solution (OM) to placebo and a positive control group receiving intravenous (IV) morphine as an add-on treatment to morphine patient-controlled analgesia (PCA) in a mixed population of paediatric and adult haematology patients. All patients in the study were equipped with a morphine PCA pump and the participating patients were instructed to use this pump as an escape. Primary outcome was morphine consumption (mg/kg/hour) on the PCA pump. Secondary outcomes included pain intensity difference at rest and when performing oral hygiene, time to first PCA bolus, nutrition intake and adverse events.

findingsA total of 60 patients (38 children <18 years) were randomized. Thirty patients were allocated to morphine OM/placebo IV (group MO), 15 patients to placebo OM/morphine IV (group MI) and 15 patients to placebo OM/placebo IV (group P). The median morphine consumption in the MO group (22.7 mcg/kg/hour 95% confidence interval (CI) 19.4-29.4 mcg/kg/hour, p = 0.38) was not significantly different from the placebo group (24.6 mcg/kg/hour 95% CI 16.8-34.4 mcg/kg/hour, p = 0.44) or the MI group (13.7 mcg/kg/hour 95% CI 9.7-37.8 mcg/kg/hour). For the secondary outcomes, the analysis of summed pain intensity difference after the first, third and fourth administrations of study medication indicated a reduction in pain for the MI group compared to the P and MO groups. No serious adverse events were reported.

conclusionThe findings indicate that the analgesic effect of peripherally applied morphine is not significantly different from placebo, and parenteral opioids should continue to be the standard of care.