Mouth ulcers are very common. They are painful, uncomfortable sores that can appear anywhere in your mouth, though they are most commonly found on the tongue (tongue ulcers) or the insides of the mouth. They’re usually round or oval shaped and appear raised and swollen. Mouth ulcers can be red, white, yellow or grey in colour. 

You can have single or multiple ulcers in your mouth and they can be very tender and sore, making it uncomfortable to eat, drink or brush your teeth. Fortunately, there are mouth ulcer treatments you can try at home that can help.


Most mouth ulcers are usually caused by damage to the mouth lining, as a result of one of the following:

  • Biting your cheek or tongue
  • Poorly fitting dentures
  • Hard, crisp, or crunchy foods that does not break down easily
  • Sharp teeth or a defective filling

Other possible causes can be stress, family history or eating certain foods that may trigger ulcers such as nuts, cheese, spicy foods, or wheat flour.


Mouth ulcers normally clear up on their own within a week or so. If they’re bothering you, you can try one of the following methods:

  1. Use an antimicrobial mouthwash, like Corsodyl 0.2% mouthwash, which can be used as an aid to heal recurring mouth ulcers.
  2. Excessive force when brushing may damage the gums leading to an ulcer. Talk to your dentist about the right toothbrush for you.
  3. Avoid crunchy, spicy, acidic, hot or salty food until your ulcer heals. 
  4. Avoid trigger foods if you find they cause ulcers. 


While most mouth ulcers are harmless, if you’re worried, if they last for more than three weeks, keep coming back or if they get worse, becoming more painful and red you should seek medical advice. 


Find out how to help protect your gums from gum disease and the importance of regular dental checkups.