Mouth ulcers

Mouth ulcers are painful breaks in the lining of the mouth. Most are simple aphthous ulcers (canker sores) — small, round, recurring but self-healing within a couple of weeks — often triggered by minor trauma (biting, a hard toothbrush), stress, hormonal changes or certain foods, and not a sign of anything serious. What raises concern is a pattern: ulcers that are unusually frequent or severe, that keep coming in crops, or that don't heal. That pattern can reflect nutritional deficiency (iron, vitamin B12 or folate), coeliac disease or inflammatory bowel disease (Crohn's, ulcerative colitis), Behçet's disease, or autoimmune conditions such as lupus. Separately, and importantly, a single ulcer that does not heal within about three weeks — especially a firm, painless one — needs to be checked to exclude mouth cancer, particularly in smokers and drinkers.

• Simple aphthous ulcers (canker sores) — the common, benign, self-healing kind; trauma, stress, hormones, some foods.
• Iron, vitamin B12 or folate deficiency — recurrent or severe ulcers.
• Coeliac disease — with other gut or nutritional features.
• Inflammatory bowel disease (Crohn's, ulcerative colitis).
• Behçet's disease — recurrent mouth and genital ulcers with other features.
• Autoimmune disease — including lupus.
• Certain medications; viral infections (e.g. herpes, hand-foot-and-mouth).
• Mouth cancer — an ulcer that fails to heal in ~3 weeks; the key reason not to ignore a persistent one.

One-off ulcers need no tests. Recurrent, severe or persistent mouth ulcers warrant blood tests looking for the treatable causes: ferritin and a full blood count (iron deficiency), vitamin B12 and folate (deficiency), and coeliac serology (anti-tissue-transglutaminase with total IgA). CRP and other tests are added if inflammatory bowel disease or an autoimmune condition is suspected from other symptoms. Mediora.AI surfaces the iron, B12, folate and coeliac pattern from your results — correcting a deficiency often resolves the ulcers; a single non-healing ulcer, by contrast, is a matter for direct examination by a dentist or doctor, not blood tests.