Mouth sores

Definition

Various types of sores can appear anywhere within the mouth, including the inner cheeks, gums, tongue, lips, or palate.

Common Causes

Mouth sores are most often mechanical irritations, cold sores (also called fever blisters), or canker sores. Irritation can happen from:

• Biting your cheek, tongue, or lip
  
• Chewing tobacco
  
• Braces
  
• A sharp or broken tooth or poorly fitting dentures
  
• Burning your mouth from hot food or drinks
  

Cold sores are caused by herpes simplex virus and are very contagious. Usually, you have tenderness, tingling, or burning before the actual lesion appears. Herpes lesions begin as blisters and then crust over.

The herpes virus can reside in your body for years, appearing as a mouth sore only when something provokes it. Such circumstances may include another illness, especially if there is a fever, stress, hormonal changes (like menstruation), and sun exposure.

Canker sores are NOT contagious and can appear as a single pale or yellow ulcer with a red outer ring, or as a cluster of such lesions. The cause of canker sores is not entirely clear, but may be related to:

• A virus
  
• A temporary weakness in your immune system (for example, from cold or flu)
  
• Hormonal changes
  
• Mechanical irritation
  
• stress
  
• Low levels of Vitamin B12 or folate
  

For unknown reasons, women seem to get canker sores more often than men. This may be related to hormonal changes.

Less commonly, mouth sores can be a sign of an underlying illness, tumor, or reaction to a medication. Such potential illnesses can be grouped into several broad categories:

• Infection (like hand-foot-mouth syndrome)
  
• Autoimmune diseases (like lupus)
  
• Bleeding disorders
  
• Malignancy
  
• Immunosuppression (that is, when your immune system is compromised - for example, if you have AIDS or are receiving medication after a transplant).
  

Drugs that might cause mouth sores include chemotherapeutic agents for cancer, aspirin, barbiturates (used for Insomnia), gold (used for ), penicillin, phenytoin (used for seizures), streptomycin, or sulfonamides.