Thrush : Causes, Symptoms, Complications and Treatments

This annoying yeast infection affects the oral cavity — specifically the mucous membranes of the mouth and tongue. It’s not uncommon to get thrush after a course of heavy-duty antibiotics, which can disrupt the natural balance of flora (bacteria) we all carry in our mouths. Thrush isn’t life-threatening, but it can be painful. Let’s look at how to cope with an episode of thrush.


As you probably know, your mouth is full of germs (bacteria). Usually, these germs live in harmony, and some of them provide a benefit to the body. For example, some benign bacteria in the mouth may help destroy other, infectious bacteria.

Among the group of bacteria that live in the mouth are fungi. One of those fungi is called ‘Candida.’ Other germs, along with our body’s immune system, normally keep Candida levels in check. If something happens to reduce the number of helpful bacteria in your mouth, Candida can multiply rapidly and cause a fungal infection called thrush. Candida is the same fungus that usually causes vaginal yeast infections.


At its core, thrush is caused by an overabundance of Candida fungi in your mouth. What can cause this to happen?

  • Taking a high dose of antibiotics that destroys the ‘friendly’ bacteria in your mouth and allows Candida to grow unchecked
  • Having a compromised immune system due to age or medical condition, which makes it harder for your body to control Candida levels on its own
  • ‘Feeding’ the Candida fungus with high sugar levels in saliva, often caused by uncontrolled diabetes
  • Taking steroid medications, which can disrupt the normal balance of flora in your mouth

Interestingly, thrush is not uncommon in infants and isn’t considered abnormal unless it lasts at least two weeks.


Thrush has some very distinctive characteristics, including:

  • Velvety white sores inside the mouth or on the tongue
  • Overall velvety, white coating of the tongue, sides of the mouth or even back of the throat
  • Swollen, tender oral tissue – particularly the tongue
  • Bleeding of the tongue
  • General painful feeling when eating, particularly anything ‘sharp’ like potato chips


You can self-treat a mild case of thrush to see if it clears up. Eat yogurt or similar products with active Lactobacillus acidophilus cultures. This method is most effective. You may also try taking acidophilus supplements, though this may be less worthwhile. Acidophilus is a naturally occurring bacterium that normally lives in our mouths. Eating acidophilus can help restore the normal balance of flora in the oral cavity.

You also may try rinsing your mouth with a diluted 3% hydrogen peroxide solution multiple times per day. Combine the hydrogen peroxide with water in a roughly 50-50 ratio. The hydrogen peroxide may destroy the Candida cells. Be careful not to swallow this concoction! Do not give this remedy to children because they may accidentally drink it.

If home remedies don’t work, you should make an appointment with your healthcare provider. He or she may prescribe medication, either an oral rinse or pills, to help clear up the thrush.


While thrush is a relatively common problem and usually remains confined to the mouth, it can spread throughout the body if left untreated. You should contact your healthcare provider if you fall into one of these groups and develop a thrush infection:

  • HIV positive
  • Undergoing chemotherapy
  • Taking immunosuppressive medications, such as those used after an organ transplant
  • Elderly
  • Infants feeding poorly due to the pain of thrush sores

In these populations thrush can spread and cause serious complications, such as meningitis (brain inflammation), endocarditis (inflammation of the lining of the heart muscle) or inflammation of the eyes.


If you’re at high risk for developing thrush, you should take precautions to avoid developing it. Some things you can do are:

  • Regularly eat yogurt or products containing active Lactobacillus acidophilus cultures
  • Replace pacifiers if your baby gets a case of thrush that requires treatment
  • Keep your blood sugar levels under control if you have diabetes
  • Be alert to signs of thrush developing so you can receive quick medical intervention
  • Get dentures fitted well; people with ill-fitting dentures risk repeated thrush infections


This oral fungal infection is a not-uncommon occurrence. Most people will experience at least one episode of thrush during their lifetime. Simply be alert to the signs of thrush and seek medical attention if home remedies don’t work. Thrush usually is triggered by a known event (such as taking antibiotics), so once it clears up you should be home free.

Image Source :James Heilman, MD  Creative Commons