Effective Treatment of Methotrexate Induced Oral Mucositis With a Morphine Mouthwash Solution: A Case Report

<b>Introduction:</b> Methotrexate (MTX) is a common medication used to treat rheumatoid arthritis (RA). MTX inhibits rapid cell turnover throughout the body which can lead to significant side effects. Patients who present with oral lesions may have suffered severe acute toxicity from MTX. Supportive pain treatment includes magic mouthwash solution and/or oral viscous lidocaine to manage pain and allow for healing. We report a case of MTX induced oral mucositis that did not respond to magic mouthwash but did improve with a morphine mouthwash solution. <b>Case:</b> A 67-year-old female with RA presented with worsening oral lesions over 2 weeks. She reported non-compliance with folic acid for 2 weeks while on MTX. Physical exam revealed ulcerating oral lesions on the mucous membranes consistent with mucositis. Pain treatment was initiated with magic mouthwash, but her pain was not well controlled after 24 hours, and still unable to swallow. An oral morphine mouthwash solution was initiated, and patient reported improved pain control over the next 48 hours. She was on the morphine mouthwash for 6 days during which improvement in the lesions was noted. <b>Discussion:</b> Pain management is imperative for oral mucositis. When traditional therapies do not provide adequate control, morphine mouthwash can be considered. It is a safer alternative to systemic opioids and topical opioids may influence cell proliferation and migration, which can positively impact healing of oral lesions. <b>Conclusion:</b> A morphine mouthwash solution can provide effective pain management for oral mucositis lesions in patients who do not respond adequately to magic mouthwash.