Intravenous Flurbiprofen Axetil Enhances Analgesic Effect of Opioids in Patients with Refractory Cancer Pain by Increasing Plasma β-Endorphin

Background: The study aimed to investigate the analgesic effect of a combination of intravenous flurbiprofen axetil and opioids, and evaluate the relationship between refractory pain relief and plasma ${\beta}$-endorphin levels in cancer patients. Materials and Methods: A total of 120 cancer patients was randomly divided into two groups, 60 patients took orally morphine sulfate sustained-release tablets in group A, and another 60 patients receiving the combination treatment of intravenous flurbiprofen axetil and opioid drugs in group B. After 7 days, pain relief, quality of life improvement and side effects were evaluated. Furthermore, plasma ${\beta}$-endorphin levels were measured by radioimmunoassay. Results: With the combination treatment of intravenous intravenous flurbiprofen axetil and opioids, the total effective rate of pain relief rose to 91.4%, as compared to 82.1% when morphine sulfate sustained-release tablet was used alone. Compared with that of group A, the analgesic effect increased in group B (p=0.031). Moreover, satisfactory pain relief was associated with a significant increase in plasma ${\beta}$-endorphin levels. After the treatment, plasma ${\beta}$-endorphin level in group B was $62.4{\pm}13.5pg/ml$, which was higher than that in group A ($45.8{\pm}11.2pg/ml$) (p<0.05). Conclusions: Our results suggest the combination of intravenous flurbiprofen axetil and opioids can enhance the analgesic effect of opioid drugs by increasing plasma ${\beta}$-endorphin levels, which would offer a selected and reliable strategy for refractory cancer pain treatment.