Antidepressant Relieves Mouth Pain from Cancer Treatment

Researchers at the Mayo Clinic have discovered that a drug used to fight depression may also help alleviate the pain from mouth sores caused by cancer treatments.

The results of a new study found that an oral rinse of the antidepressant doxepin significantly eased pain from oral mucositis in patients receiving radiation treatments for cancers of the head and back.  The findings suggest that doxepin rinse could be an alternative to narcotic painkillers in treating mouth sores.

“Oral mucositis or mouth sores is a painful and debilitating side effect of radiation therapy,” said principal investigator Robert Miller, MD, a radiation oncologist at Mayo Clinic. “Our findings represent a new standard of care for treating this condition.”

155 patients receiving radiation therapy for head and neck cancer took part in the Phase III study comparing the effectiveness of doxepin oral rinse versus a placebo.

The patients received a single dose of doxepin on the first day, then took a placebo the next day. On a scale of 0 to 10 administered at baseline, patients reported pain associated with oral mucositis, then at increasing intervals of five, 15, 30, 60, 120 and 240 minutes after rinsing with doxepin.

“In comparison to a placebo, we found that patients who didn’t know what they were rinsing their mouth with, the patients that received the drug doxepin had less pain then those who received the placebo,” said Miller.

Patients were given the option o taking doxepin after the study and 64 percent did so. Researchers say doxepin was well tolerated, though stinging, burning, unpleasant taste and drowsiness were reported as side effects.

One newly discovered side effect of doxepin is hair loss. In a separate study, scientists at the University of Melbourne found that a number of drugs, including those for blood pressure, acne, and depression, can lead to hair loss.

“When drugs do affect the hair, the change is usually mild and reverses when the drug is stopped,” said  Sam Shuster, professor of dermatology at Newcastle University.” So you may want to tolerate the change, because of the important effect the drug is having in restoring your health.”

Doctors at the Mayo Clinic say that mouth sores are a common problem for cancer patients undergoing chemotherapy and radiation. Both treatments can impair the body’s mmune system, allowing viruses, bacteria and fungi to more easily infect the mouth.

The sores can appear on any of the soft tissues of the lips or mouth and can be painful, making it difficult to eat, talk, swallow and breathe. Sores from radiation may last four to six weeks after the treatment ends.

The findings were presented at the American Society for Radiation Oncology annual meeting in Boston.

Authored by: Richard Lenti