History and types
"Aphtha" comes from the Greek for "to set on fire," Hippocrates' word for burning mouth sores. Recurrent aphthous stomatitis, affecting about 20% of people, produces round ulcers under 1 cm with a white center and red rim that heal on their own in one to two weeks. Clusters of blisters on lips and gums suggest herpetic stomatitis from herpes simplex, while frequent ulcers with eye, skin or genital symptoms raise suspicion of Behçet's disease.
Causes
The exact cause is unknown, but a disordered immune response combined with fatigue, stress, poor sleep, minor injury from brushing or biting, and menstrual cycles is typical. Iron, vitamin B12 or folate deficiency, iron-deficiency anemia and toothpastes containing sodium lauryl sulfate have also been linked.
Treatment and care
Most heal unaided, but steroid gels, antiseptic rinses and protective patches ease pain and speed healing. Avoid spicy, salty or hot food, alcohol and smoking, and get enough sleep. See a clinician if an ulcer lasts more than two weeks, is large and painless, or recurs many times a year, to rule out oral cancer or systemic disease.
This article is general health information and is not a substitute for diagnosis or treatment. If symptoms persist, see a doctor.
FAQ
- Are mouth ulcers contagious?
- Aphthous ulcers are not, but herpetic stomatitis can spread through saliva and contact.
- Do vitamins prevent them?
- They may help people with a deficiency, but benefit is unclear otherwise.
Sources reviewed: 2026-10-26
References
- Scully, C., & Porter, S. (2008). Oral mucosal disease: Recurrent aphthous stomatitis. British Journal of Oral and Maxillofacial Surgery, 46(3), 198–206.
- Edgar, N. R., Saleh, D., & Miller, R. A. (2017). Recurrent aphthous stomatitis: A review. Journal of Clinical and Aesthetic Dermatology, 10(3), 26–36.
- 질병관리청 국가건강정보포털. (2024). 구내염.