Mouth ulcers

Mouth ulcers are painful small spots on the lining of the mouth in particular.


Mouth ulcers are painful small spots on the lining of the mouth in particular. They are round, sharply outlined and yellowish-grey in colour. Causes can include, for example, malnutrition or specific underlying diseases. A generally healthy lifestyle (sufficient sleep, balanced diet) can have a preventive effect.


  • Painful spots on the lining of the mouth and throat
  • Skin change
    • Round to oval
    • Sharply outlined, crater-shaped
    • Yellowish-grey in colour
  • Minor ulcer
    • Diameter of up to 1 cm
    • Usually heals on its own within 1 to 2 weeks
    • Doesn't form a scar
  • Major ulcer (more rarely):
    • Diameter of up to 3 cm
    • Can take several weeks to heal
    • Forms a scar

Causes and treatment


Further treatment by your doctor / in hospital

Possible tests
  • Examination of mouth and throat
Possible therapies
  • Tea tree oil: Topical application, has an antiseptic (disinfecting) effect
  • Rinsing the mouth with chamomile or sage tea (also disinfecting)
  • Ointment, spray or gel with lidocaine (local analgesic)
  • Astringent tinctures (slightly caustic substances):
    • Rhubarb root extract, silver nitrate
    • Have a positive effect on the healing process
  • Use cotton wool to dab the ulcer dry before applying any products
  • Medical or dental intervention is often needed to heal major ulcers (e.g. laser therapy)

What can I do myself?

  • Sufficient sleep, relaxation
  • Balanced, vitamin-rich diet
  • Optimised treatment for any underlying disease
  • Change to toothpaste that doesn't contain sodium lauryl sulphate

When to see a doctor?

  • Very frequent occurrence (approx. every two months, repeatedly)
    • To diagnose an underlying disease, if any
  • Doesn’t heal after 1 to 2 weeks
  • Grows into a major ulcer
  • Children with several ulcers and fever
    • Possible, initial infection with the herpes simplex virus (aphthous stomatitis, very painful)


mouth ulcers, mouth ulcer

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CSS offers no guarantee for the accuracy and completeness of the information. The information published is no substitute for professional advice from a doctor or pharmacist.