The patient complains of a painful lesion in the mouth, and may be worried about having herpes. A pale yellow, flat, even-bordered ulcer surrounded by a red halo may be seen on the buccal or labial mucosa, lingual sulci, soft palate, pharynx, tongue, or gingiva. Lesions are usually solitary, but can be multiple and recurrent. The pain is usually greater than the size of the lesions would suggest, and major aphthae (larger than 1 cm) indicate a severe form of the disease which may last for weeks of months.
What to do:
Attempt to differentiate from lesions of herpes simplex and reassure the patient of the benign nature of most canker sores.
Inform the patient that these lesions usually last 1-2 weeks, and that they should avoid hot, acidic or irritating food and drink.
For transient pain relief, try a tablet of sucralfate crushed in a small amount of warm water, swirled in the mouth or gargled. Tetracycline elixir (or a capsule dissolved in water) not swallowed, but applied to cauterize lesions or used as a mouth wash can relieve pain after single or repeated application. Benadryl elixir mixed one-to-one with Kaopectate, Xylocaine 2% Viscous Solution, and Orabase HC applied topically can also provide symptomatic relief.
For more severe cases, prescribe triamcinolone acetonide 0.1% suspension (add injectable Kenolog to sterile water without preservatives) in a 5ml oral rinse and spit out four times a day after meals and before bed, taking nothing by mouth for an hour afterward. An alternative regimen is dexamathasone elixir 1.5mg in 15ml qid rinse and swallow, tapering to three days of 0.5ml in 5ml, then three days swallowing every other dose, but discontinuing the regimen as soon as the mouth becomes comfortable.
In very severe cases, try a burst dose of prednisone 40-60mg qd x5 (no tapering).
Aphthous stomatitis has been studied for many years by numerous investigators. Although many exacerbating factors have been identified, the cause as yet remains unknown. Lesions can be precipitated by minor trauma, food allergy, stress, and systemic illness. Recurrent aphthous ulcers may accompany malignancy or autoimmune disease. At present, the treatment is only palliative, and may not
alter the course of the syndrome. Apthous ulcers may be an immune reaction to damaged mucosa or altered oral bacteria. Herpangina and hand-foot-and-mouth disease can produce ulcers resembling aphthous ulcers, but which are instead part of coxsackie
viral exanthems, usually with fever and occurring in clusters among children. Behcet's syndrome is an idiopathic condition characterized by oral ulcers clinically indistinguishable from aphthae but accompanied by genital ulcers, conjunctivitis, retinitis, iritis, leukocytosis, eosinophilia and increased erythrocyte sedimentation rate.
Vincent SD, Lilly GE: Clinical, historic and therapeutic features of aphthous stomatitis. Oral Surg Oral Med Oral Pathol 1992;74:79-86.