Canker sores (aphthous ulcers) are painful ulcers that occur in
the lining of the mouth. Ulcers are not cancerous, but they may be
contagious. The mouth and adjacent areas are involved. Canker sores can
affect both sexes, all ages, but is more common in females. The typical
appearance involves an erythematous periphery with a white or yellow
depressed center. Healing within 10 to 14 days is the rule.
Causes: Viral (coxsackievirus, herpesvirus), systemic illness
(Crohn's disease, lupus, Behcet's disease, erythema multiforme),
toothpaste (sodium lauryl sulfate), stress, and smoking. Dental trauma,
vitamin B12, folate, and iron deficiency have also been implicated in
some cases.
Treatment: Symptomatic relief can be obtained by the use of
diphenhydramine elixir as a mouth rinse that is then xpectorated.
Alternatively, viscous lidocaine 2% can be used in the adult. This may
suppress the gag reflex, however, and may result in systemic toxicity
in children. The application of a topical steroid (triamcinalone as
0.1% in Orabase) or steroid mouth rinse (betamethasone syrup) may
accelerate recovery. Herpetiform ulcerations may respond to
tetracycline syrup, which is used as a mouth rinse and then swallowed.
A burst of oral prednisone may be required in some cases. The use of
multiple other drugs including cyclosporin A, colchicine, thalidomide,
and dapsone attest to the stubborn nature of these lesions. A mixture
of nystatin 12,500 units, diphenhydramine 1.25 mg, and hydrocortisone
0.25 mg/ml has been used as a "shotgun" solution. Some also include
tetracycline syrup in the mixture.
Prevention: Using a toothpaste free of sodium lauryl sulfate
or changing toothpastes has been shown to be helpful in some cases.
Topical use of steroids, mouth rinses, may decrease recurrence.
Recently, pentoxifylline has been used to prevent recurrent aphthous
ulcers in an open label trial. However, blinded studies are lacking.
Herpes simplex virus infrequently
causes recurrent intraoral herpes. The lesions occur as a cluster of
vesicles that rupture leaving superficial ulcerations that remain for 3
to 10 days. Keratinized tissues, attached gingiva, and the hard palate
are often involved, and such features distinguish herpes from aphthous
ulcers. Treatment with acyclovir may decrease healing time.
Findings of a study show that 90% of HIV-positive patients with
aphthous ulcers of the mouth and oropharynx have at least partial
healing in response to treatment with thalidomide.
Dr. Jeffrey M. Jacobson of the Bronx Veterans Affairs Medicine
Center in New York City and colleagues at 19 sites treated 29
HIV-positive patients with 200 mg thalidomide or placebo daily for 4
weeks. All subjects had biopsy-confirmed oral aphthous ulcers at least
2 weeks prior to treatment. The double-blind, randomized study was part
of the AIDS Clinical Trials Group protocol 251 sponsored by the
National Institute of Allergy and Infectious Diseases. In addition to
weekly evaluations of the subjects` clinical status, quality of life
and evidence of drug toxicity, the researchers also measured plasma
tumor necrosis factor alpha (TNF-alpha), soluble TNF-alpha receptors
and HIV RNA.
Dr. Jacobson reports that by 4 weeks, 55% of treated subjects
experienced complete healing of their ulcers, compared with 7% in the
placebo group. Some patients had complete healing as early as 1 week.
The subjects also reported less pain and were better able to eat.
Treatment side effects included somnolence and rash, and toxicity
necessitated treatment discontinuation in six subjects.
According to Dr. Jack Y. Killen, director of the Division of AIDS at
the National Institute of Allergy and Infectious Diseases in Bethesda,
Maryland, "thalidomide is the first treatment shown in a scientific
study to heal these ulcers." He also cautioned that thalidomide
treatment should be carefully monitored and limited in its duration
because of the drug's potential toxicity.
- Mark A. Graber, M.D. and Laura Beaty, M.D. Otolaryngology: Tongue
and Mouth. University of Iowa Family Practice Handbook, 3rd Edition,
Chapter 19
