Oral mucositis may occur as a side effect of radiotherapy for head and neck tumors. This is frequent, sometimes extremely painful and clearly limits the therapeutic options. Pain-relieving medications are usually used, although it is not uncommon for opioids to be used in severe forms. One study now examined the effect of flushing with doxepin, a tricyclic antidepressant.
The randomized phase III study of 155 patients with radiotherapy-induced mucositis pain was published in the Journal of Clinical Oncology [1]. Participants received either a single dose of oral doxepin flush or placebo on the first day. They had to keep them in their mouths for one minute each. On the following day, medication was changed according to the crossover design. Pain was assessed via a questionnaire at baseline and then after 5, 15, 30, 60, 120, and 240 minutes. After that, patients could choose for themselves whether to continue taking doxepin.
Relevant pain reduction
The primary endpoint was pain reduction. This was determined on day 1 using the so-called area under the curve (AUC) of the pain scale. Mouth and throat pain reduced significantly more with doxepin (-9.1) than with placebo (-4.7, p<0.001). When the first day was compared with the second, there was a 4.1 increase in pain from switching from doxepin to placebo and a -2.8 reduction from placebo to doxepin. This difference was also significant. Side effects that occurred more frequently with the verum were a stinging or burning sensation, unpleasant taste, and greater drowsiness.
Because of the relevant pain relief, many patients indicated that they wanted to continue doxepin irrigation. Overall, therefore, the authors certainly see potential for using the agent to manage the severely limiting mucositis pain associated with radiotherapy. At least over the four hours measured, doxepin appears to provide notable analgesia.
Literature:
- Leenstra JL, et al: Doxepin rinse versus placebo in the treatment of acute oral mucositis pain in patients receiving head and neck radiotherapy with or without chemotherapy: a phase III, randomized, double-blind trial (NCCTG-N09C6 [Alliance]). J Clin Oncol 2014 May 20; 32(15): 1571-1577.
InFo ONCOLOGY & HEMATOLOGY 2015; 3(3-4): 2
