Mouth Ulcers

Despite the common occurrence of mouth ulcers and vast amounts of research, the cause of these irritating sores is still not completely understood. However, by far and away the most common cause is the infection of an injury in the mouth. These injuries can be cuts, abrasions or burns.

A mouth ulcer affects the softer areas of the mouth, for example the tongue and cheeks. The surface layer of the skin is removed leading to the formation of the ulcer which usually appears circular with a yellow or white centre and a raised red rim. It is because of the removal of the skin layer that nerve cells are exposed causing the associated pain.

You should not attempt to treat a mouth ulcer yourself if:

  • you are pregnant
  • you are diabetic
  • the ulcer has an uneven colouration
  • the ulcer is causing you no discomfort or pain
  • it is your first mouth ulcer
  • it has been present for more than 14 days
  • it is larger than 1cm in diameter
  • you take any other medication


There are many types of treatment available. These can be placed into three main categories:

Pain Relief

These products contain ingredients which act to prevent the sensation of pain. They usually contain an anaesthetic which is applied directly to the ulcer. After some initial stinging while the anaesthetic starts to work the area will become numb.
Care should be taken with hot food and drinks as further damage can be caused to the ulcer while it is numb.

Some examples of the anaesthetics used are benzocaine and lidocaine.

Also available is an ingredient called choline salicylate which is related to aspirin. This pain killer works at the site of the ulcer in the same way as the analgesics or pain killers. This means that they are generally longer acting than the anaesthetics.

Choline salicylate should not be used by people allergic to aspirin.


These treatments are used to kill any bacteria that may be infecting the ulcer or more generally the entire mouth. They are usually mouth washes if the antibacterial is the only active ingredient although they are often incorporated into the other treatments, for example, pain relief treatments.


These are the newest treatments available for mouth ulcers, they are based on corticosteriods which act to reduce the inflammation at the site of the ulcer and as such aid healing.

It is important to note that the use of these locally acting products avoids many of the associated side effects of oral corticosteriods.

General Advice

There are some simple things you can do to reduce the discomfort felt while you have a mouth ulcer.

Firstly, do not expose the ulcer to foods which cause pain and aggravate the symptoms. These types of food are acidic, spicy, salty, coarse or hot and cold. However it may be of some benefit to gargle with salt water as this is mildly antibacterial.

You can also use mouth washes regularly to prevent mouth ulcers if you find that you are getting mouth ulcers regularly.

You should consult your doctor if the problem persists..

Patient Information Home Page

PharmWeb® - Copyright©1994-2016. All rights reserved

The advertisements on
this page are not reviewed
by PharmWeb.