Sores on Tongue: 5 Common Causes & What to Do

Medical review: Dr. Gonzalo Ramirez
General Practitioner and Psychologist
November 2022
  1. Medication
  2. Thrush
  3. Aphtous stomatitis 
  4. Herpes
  5. Leukoplakia

Sores on the tongue can occur as a side effect of medication or it can be a sign of aphtous stomatitis (which is a condition characterized by having canker sores more than twice in a month).

These sores can also appear with oral thrush, leukoplakia or oral herpes, although these conditions will usually cause other symptoms, like mouth swelling, white spots and difficulty swallowing. 

If you notice sores on the tongue, you should see your dentist, family doctor or gastroenterologist for assessment so that treatment can be started as necessary. 

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Causes of sores on the tongue

The main causes of sores on the tongue are:

1. Use of medication

Some medications can causing burning in the throat as a side effect. These medications can cause discomfort to the tongue, palate, gums, inner cheeks and throat, which can last for the full duration of treatment. 

What to do: It is important to report medication side effects, like burning, to your doctor so that the doctor can evaluate the need to discontinue, swap or alter the dose of your medication. 

2. Oral thrush

Oral thrush is a fungal infection caused by Candida albicans fungus. This fungus can grow and spread in the mouth and throat, and cause symptoms like white plaques within the mouth, sore throat, difficulty walking and cracks in the corners of the mouth. 

Orla thrush usually emerges when the immune system is weakened. This is why this condition is commonly seen in babies, older adults, in people with are immunosuppressed (e.g. AIDS patients), and in those with a history of diabetes or cancer treatment. 

What to do: Treatment for oral thrush should be monitored by a doctor, who will likely prescribe antifungals, like nystatin or miconazole. This medication can be provided in liquid, cream or gel form for direct application to the sores. 

3. Aphtous stomatitis 

Aphtous stomatitis is characterized by the presence of canker sores, blisters or wounds in the mouth that emerge more than twice a month. The canker sores develop as small wounds that are white or yellow in color with a red border. They can occur on the inner cheeks, lips, gums and throat. 

This condition can emerge due to a sensitivity to specific foods, or due to a vitamin B12 deficiency, hormonal changes, stress or a weakened immune system. 

What to do: It is important to consult a doctor or dentist if you commonly experience canker sores. Treatment is aimed at relieving pain and discomfort and well as healing the wounds. The doctor or dentist may recommend anti-inflammatories, analgesics, and in some cases, antibiotics. These can be prescribed as an oral rinse to disinfect the entire mouth and relieve pain.

4. Oral herpes

Oral herpes is a viral infection that causes blisters and crusting lesions. These sores usually appear on the lips, but can also grow below the nose, on the chin or even on the tongue or inner mouth, making it difficulty to swallow. Oral herpes blisters can rupture, and any fluid released can contaminate surrounding areas. 

What to do: Oral herpes is not curable, however symptoms can be managed and a flare-up can be prevented. The doctor may prescribe a topical antiviral cream, like acyclovir. 

5. Leukoplakia

Oral leukoplakia is characterized by the emergence of small white plaques that grow on the tongue and can spread to the inner cheeks or gums. These plaques usually do not cause any symptoms and disappear without any treatment. 

Leukoplakia can be caused by a vitamin deficiency, inadequate oral hygiene, dental work, ill-fitting dentures, cigarette use, HIV infection or Epstein-Barr infection. 

What to do: It is important to consult a doctor if you notice white plaques in the mouth, so that they can be assessed and treated as necessary. Treatment depends on the underlying cause. If the doctor suspects it is related to mouth cancer, the doctor may order a biopsy to remove and analyze the affected cells, as well as cryotherapy. It can also be treated with antiviral medications, like valacyclovir or fancyclobir, or medications that contain podophyllum resin or tretinoin. 

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Edited by Tua Saude editing team in November 2022. Medical review completed by Dr. Gonzalo Ramirez - General Practitioner and Psychologist in November 2022.


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Medical review:
Dr. Gonzalo Ramirez
General Practitioner and Psychologist
Dr. Ramirez possesses a medical degree from the Universidad Popular Autónoma del Estado de Puebla (UPAEP). He also specializes in clinical psychology.