Dexamethasone is a corticosteroid. Steroid-containing oral pastes or rinses have been used to treat aphthous ulcers (Divers & O'Shaughnessy, 2015; Nicolatou-Galitis et al., 2013; Pilotte et al., 2011; Rugo et al., 2017), also known as canker sores (Mayo Clinic, 2018), and are being studied in the treatment of cancer treatment-related mucositis.

Divers, J., & O’Shaughnessy, J. (2015). Stomatitis associated with use of mTOR inhibitors: Implications for patients with invasive breast cancer. Clinical Journal of Oncology Nursing, 19, 468–474.​ https://doi.org/10.1188/15.CJON.468-474

Mayo Clinic. (2018, April 3). Canker sore. Retrieved from https://www.mayoclinic.org/diseases-conditions/canker-sore/symptoms-cau…

Nicolatou-Galitis, O., Nikolaidi, A., Athanassiadis, I., Papadopoulou, E., & Sonis, S. (2013). Oral ulcers in patients with advanced breast cancer receiving everolimus: A case series report on clinical presentation and management. Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology, 116, e110-e116. https://doi.org/10.1016/j.oooo.2013.02.022

Pilotte, A.P., Hohos, M.B., Polson, K.M., Huftalen, T.M., & Treister, N. (2011). Managing stomatitis in patients treated with Mammalian target of rapamycin inhibitors. Clinical Journal of Oncology Nursing, 15, e83–e89.​ https://doi.org/10.1188/11.CJON.E83-E89.

Rugo, H.S., Seneviratne, L., Beck, J.T., Glaspy, J.A., Peguero, J.A., Pluard, T.J., . . . Litton, J.K. (2017). Prevention of everolimus-related stomatitis in women with hormone receptor-positive, HER2-negative metastatic breast cancer using dexamethasone mouthwash (SWISH): A single-arm, phase 2 trial. Lancet.Oncology, 18, 654–662. https://doi.org/10.1016/S1470-2045(17)30109-2