Oral thrush can be a common condition for people with conditions that suppress the immune system, such as HIV. It’s estimated that about 80 to 90 percent of people with HIV will deal with thrush in the mouth or throat at some point in their lives.

Oral thrush is a yeast infection that causes white or yellowish bumps and patches inside your mouth. It’s most often caused by fungus in the genus Candida.

Candida live in the mouths of most people without causing any symptoms. But for people with compromised immune systems, like those living with HIV, the fungus may spread quicker than the immune system can fight it off.

Keep reading to learn everything you need to know about the connection between oral thrush and HIV.

Oral thrush is medically known as oropharyngeal candidiasis. It’s an overgrowth of yeast in your mouth that leads to yellow or white bumps or patches. These can appear on your inner cheeks, lips, tonsils, or tongue.

Thrush can often cause other symptoms like a sore throat or trouble swallowing.

Oral thrush is typically caused by the fungus Candida albicans, but it can also be caused by other Candida species.

About 75 percent of people have Candida in or on their bodies. It’s normal to find it on your skin or in your mouth, gut, or vagina. Usually, it doesn’t cause symptoms because your immune system is able to keep it from spreading.

People with suppressed immune systems, such as people living with HIV, people undergoing radiation or chemotherapy, infants, and older adults are most likely to get oral thrush because their immune systems are less able to control the fungus.

Chronic use of steroids or antibiotics may also increase your risk of developing oral thrush.

Pictures of oral thrush

People with HIV are prone to oral thrush because the virus weakens the immune system. It’s often among the first symptoms of HIV. It can also be a sign that you’re at risk of developing more severe infections.

Opportunistic infections

Oral thrush is known as an opportunistic infection. The Centers for Disease Control and Prevention (CDC) defines an opportunistic infection as an illness that occurs more frequently or more severely in people with HIV due to their comprised immune system.

In a 2016 study examining more than 60,000 people in the United States and Canada with HIV from 2000 to 2010, researchers found that 9 percent of people developed at least one opportunistic infection.

While opportunistic infections still occur in people with HIV, they are becoming less common because of early detection and effective HIV treatments.

Stages of HIV

HIV progresses over several stages:

  • Acute HIV infection. At 2 to 4 weeks after contracting HIV, some people develop flu-like symptoms such as a fever, fatigue, and chills. Other people don’t show any symptoms.
  • Latency period. After initial exposure, HIV lies dormant for up to 10 to 15 years. During this period, the virus replicates very slowly and may not show any symptoms.
  • Stage 3 HIV. If HIV goes untreated, the immune system will eventually weaken. A diagnosis of stage 3 HIV, or AIDS, is indicated when a level of a type of white blood cell called T cells (also called CD4 cells) drops under 200 cells per cubic millimeter of blood, or if an opportunistic infection develops.

As HIV progresses and the immune system becomes more comprised, the risk of developing oral thrush increases.

The standard treatment for oral thrust is antifungal drugs. However, long-term use of these drugs to prevent infection isn’t recommended because it can potentially lead to fungal resistance.

There hasn’t been a lot of research on how to prevent oral thrush in people at high risk of developing it. But taking good care of your overall mouth health may help. Things you can do include:

  • using a soft toothbrush
  • cleaning between your teeth, such as with floss
  • using mouthwash
  • visiting your dentist regularly
  • taking good care of dentures if you have them

Drinking plenty of fluids may help prevent oral thrush by helping you avoid mouth dryness.

A 2019 review of studies found some evidence that probiotics may help prevent oral thrush, especially in denture wearers. However, the authors report that their results should be interpreted with caution, as there are few studies available and many of the published studies have a high risk of bias.

The hallmark symptom of oral thrush is bumps or patches in your mouth that appear yellow or white. These bumps or patches can appear on your lips, tonsils, tongue, or gums.

Other symptoms of oral thrush include:

It’s important to seek treatment for oral thrush as soon as you notice it.

The first step to treating oral thrush is to address the underlying cause.

In the case of HIV, antiretroviral therapy suppresses levels of the virus and strengthens the immune system. Antiretroviral therapy is a cocktail of medications used to stop the replication of the virus and prevent the progression of HIV.

For directly targeting oral thrush, the usual treatment is antifungal medication. Oral fluconazole at a dosage of 100 milligrams (mg) once per day is the standard treatment, except in those who are pregnant.

If the infection is in your mouth, you’ll likely undergo treatment for 2 weeks. If it’s in your throat, treatment will likely be 2 to 3 weeks.

If your infection doesn’t respond to fluconazole, your doctor may recommend a different treatment. Other options found to be effective include:

  • 50-mg miconazole tablets once per day
  • 10-mg clotrimazole lozenges five times per day
  • 200 mg of itraconazole oral solution daily
  • 400 mg of oral posaconazole suspension twice daily for the first day and then once per day
  • 4 to 6 milliliters nystatin suspension four times per day
  • topical 0.00165 percent gentian violet twice per day

If you’re having severe or frequent oral thrush reoccurrences, your doctor may recommend a longer course of antifungal medications. However, doctors often try to avoid long-term use when possible since there’s a risk the fungus will become resistant to the medication.

Oral thrush symptoms often show improvement within 2 to 3 days after treated with antifungal medications. The infection usually clears up completely in less than 2 weeks.

Researchers of a 2017 study compared the effectiveness of the antifungal medicines fluconazole and clotrimazole in a group of 180 patients with oral thrush. The researchers found fluconazole was 89.5 percent effective while clotrimazole was 86.7 percent effective.

If the antifungal medicine you’re taking to target oral thrush isn’t effective, your doctor may recommend trying a different kind.

Only about 4 to 5 percent of people with HIV don’t respond to antifungal treatment. Most nonresponders have a CD4 count of fewer than 50 cells per cubic millimeter of blood.

If antifungal medications aren’t effective, your doctor may recommend amphotericin B administered through an IV.

For those with HIV not taking antiretroviral therapy, antifungal treatment might cause short-term relief, but the infection will likely come back. As HIV treatment can strengthen the immune system and suppress the virus, it’s the key to avoiding reoccurring or chronic thrush infections.

Oral thrush is a yeast infection that’s most often caused by the fungus Candida albicans. People with HIV or other conditions that suppress the immune system are at a heightened risk of developing oral thrush.

If you have HIV and develop oral thrush, it’s important to see a doctor right away. They’ll likely prescribe an antifungal medication.

Antifungal medication is usually effective for clearing an oral thrush infection. However, you should seek treatment as soon as possible if you notice symptoms.

If you notice symptoms of oral thrush and think you might also have HIV, talk with a doctor or healthcare professional about testing and treatment options.