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Skin concerns

Mouth ulcers

Small painful ulcers in the mucosa of the mouth. Recurrents in many people. It benefits from evaluation when they are very frequent or intense.

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What are canker sores

Mouth ulcers are small superficial ulcers that appear in the mucosa of the mouth — especially in the inner part of the lips, cheeks, tongue, and palate. They are very common: about 20% of people will have recurring mouth ulcers throughout their lives.

Although usually benign, they are painful and can interfere with food and speech. They are distinguished from the lesions caused by herpes — which appear outside the lips or near — by their location strictly in the oral mucosa.

Signs and symptoms

  • Feeling sting or burn before the appearance of the injury.
  • Small round ulcer with off-white or yellow background and red halo.
  • Localised pain, aggravated by chewing, speaking or contact with acids.
  • Usually 3-10 mm in diameter in common shapes.
  • Spontaneous scarring in 7-14 days without leaving a mark (in common forms).
  • Larger or multiple forms — in major and herpetiform variants, rarer and more uncomfortable.

Causes and triggering factors

  • Local trauma (bites, dental prostheses, aggressive brushing).
  • Emotional Stress.
  • Hormonal changes (menstrual cycle in some women).
  • Vitamin or iron deficits in some cases.
  • Some foods — nuts, chocolate, pineapple — in sensitive people.
  • General disorders in persistent or very recurrent conditions (celliac disease, Crohn's disease, Behcet syndrome).

Diagnosis

The diagnosis is clinical. In an online consultation, the dermatologist evaluates photographs in good lighting and a questionnaire on frequency, number, size and triggering factors. In very recurrent cases, extensive or associated with other symptoms, analysis-oriented investigation may be recommended.

Options for treatment

Most mouth ulcers resolve spontaneously. Treatment aims to relieve pain and accelerate healing.

Local care

There are local care that relieves symptoms — avoiding food that aggravates (acids, spicy, very hot), good oral hygiene with a soft product. The dermatologist may indicate specific formulations.

Investigation of underlying causes

In very recurrent or atypical situations, the dermatologist guides the investigation of possible causes — nutritional deficits, systemic diseases — in coordination with the family doctor if necessary.

Identify personal triggers

Keeping a simple journal of outbreaks helps to identify patterns — food, stress, hormonal cycle — that can be avoided or managed.

Talk to a dermatologist about your mouth ulcers

No months-long wait for an in-person appointment. Each case reaches the dermatologist already prepared with photographs, history and questionnaire answers. Choose a report in under 24h or a booked video consultation.

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Frequently asked questions

Are the mouth ulcers the same as herpes labial?

Nope. The mouth ulcers appear inside the mouth (mucosal) and are not caused by viruses. Herpes labial appears outside the lip, caused by herpes simplex virus, with vesicles in bunch — clinically very different.

Frequent affections are a sign of something more serious?

Usually not, but in persistent, very recurrent conditions, with mouth ulcers greater or associated with other symptoms (abdominal pain, weight loss), it is justified to investigate underlying causes.

How long does it take?

Common mouth ulcers resolve spontaneously within 7-14 days, without scarring. The larger forms may take longer and leave a mark — in these cases, assessment by a dermatologist is useful.

Is the online consultation for canker sores?

Yes, especially for recurring or disturbing cases. The dermatologist evaluates by photography, discusses the triggers and proposes a plan.

Relieve and prevent recurrent pains

Send photos and answer the questionnaire. A dermatologist analyzes and proposes the plan — on average 24 hours useful.