HIV weakens the immune system and increases the risk of infections, such as oral thrush. Over 90% of people with HIV may develop oral thrush at some point.

Candida is a yeast occurring in the body. In most cases, it does not cause any problems. In people with HIV, the immune system may not be able to control the growth of Candida yeast in the body, resulting in oral thrush.

This article looks at the connection between oral thrush and HIV.

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Oral thrush may occur in people with a weakened immune system, and over 90% of people with HIV may develop oral thrush at some point.

Candida, the yeast that causes oral thrush, occurs throughout the body and thrives in moist environments such as the mouth.

Usually, the immune system will prevent Candida from multiplying and growing out of control. So in most people with a healthy immune system, it does not cause any issues.

HIV weakens the immune system, making it harder for the body to fight infections. This can result in excessive Candida growth, which can cause oral thrush in the mouth.

Does having oral thrush always mean HIV?

According to the Centers for Disease Control and Prevention (CDC), oral thrush is rare in people with a healthy immune system. Oral thrush is one of the most common infections affecting people with HIV, but it can also occur for other reasons.

Other conditions that weaken the immune system may cause oral thrush, such as diabetes.

Dentures and antibiotic use may also result in oral thrush. A change in the normal balance of microbes within the body can enable an overgrowth of Candida and lead to oral thrush.

Although an overgrowth of the yeast Candida causes oral thrush, some factors can increase the risk.

These include:

There are steps people with HIV can take to help prevent oral thrush.

Antimycotics are antifungal medications that can help stop the growth of fungal infections such as oral thrush.

Fluconazole is the only effective antimycotic for preventing oral thrush in people with HIV. People take fluconazole orally as a tablet, so it affects the whole body. It may cause side effects such as:

Practicing good oral hygiene may also help, including:

  • using a soft toothbrush
  • cleaning between the teeth, such as with floss
  • using an antiseptic mouthwash
  • attending routine dentist check-ups
  • if wearing dentures, cleaning them regularly and ensuring that they fit correctly
  • drinking plenty of fluids throughout the day to help prevent dry mouth

According to the National Institute of Dental and Craniofacial Research (NIDCR), people with HIV have an increased risk of mouth problems. This is due to a weakened immune system, making it more difficult to fight off infections.

The most common oral health issues that may affect people with HIV include:

Combination antiretroviral treatment helps support the immune system in people with HIV and may reduce the likelihood of developing certain mouth conditions.

People can contact a doctor or dentist for effective treatments for mouth problems.

This section answers some frequently asked questions about oral thrush and HIV.

Can you have oral thrush and be HIV negative?

Although oral thrush is common in people with HIV, it can also occur due to various other factors. It is possible to have oral thrush and be HIV negative.

In a 2018 study of 116 people in Iran, researchers studied the occurrence of oral thrush in people both with and without HIV.

The study found that factors such as age, oral hygiene, sexual behaviors, and lifestyle may play a role in the development of oral thrush, either with or without HIV present.

If people test negative for HIV, it may still be possible to have HIV. There is a window of time in which the test may not be able to detect HIV in the body after exposure to the virus.

It is important that people get another test after the window period to confirm a negative result.

What does oral thrush look like with HIV?

Oral thrush may affect the mouth, throat, and esophagus in people with HIV. Oral thrush in the esophagus, the tube connecting the throat and stomach, is one of the most common infections to affect people with HIV.

Symptoms of oral thrush in the mouth, throat, and esophagus may include:

  • white patches in the mouth, which may appear on the tongue, inner cheeks, roof of the mouth, and throat
  • soreness or redness in the mouth
  • dryness or cotton-like sensation in the mouth
  • pain or difficulty eating or swallowing
  • loss of taste
  • cracked corners of the mouth

How soon after HIV do you get oral thrush?

According to a 2018 study, oral thrush usually occurs in the first stage of an HIV infection.

People may develop oral thrush if their levels of CD4 T lymphocytes (CD4 cells) drop to 350 colony-forming units per milliliter (CFU/mL). A CD4 cell count of 200 CFU/mL or less may cause oral thrush to affect the esophagus.

CD4 cells are a type of immune cell, which HIV destroys to weaken the immune system.

Oral thrush is common with HIV, as a weakened immune system makes it more difficult to fight off infections.

Oral thrush can occur due to causes other than HIV. Oral thrush may be a sign of a health issue though, so it is important to contact a doctor to find out the underlying cause.