Thrush, also called candidiasis, is a disease caused by a fungus (Candida albicans). Everyone has this fungus both on and inside their bodies. It can be found on the skin, in the stomach, the colon and rectum, the vagina, and in the mouth and throat. Most of the time, Candida albicans is harmless and actually helps keeps bacteria levels in check. Sometimes, however, there is an overgrowth of this fungus, which can lead to a variety of problems.
Both HIV-positive and HIV-negative people can develop candidiasis. Many women experience vaginal yeast infections, a type of candidiasis. Similarly, a person can experience an overgrowth of fungus in their mouth or the back of their throat. Stress, poor diet, or not getting enough rest can contribute to these problems. Also, a person who takes antibiotics for bacterial infections, especially for long periods of time, can develop thrush in their mouth or vagina. Candidiasis in the mouth (oral thrush) can also occur in people who use inhaled steroids, such as those used to treat asthma and other lung problems.
Poor oral hygiene and smoking can also play a role in fungal overgrowth in the mouth. Excessive alcohol and sugar consumption have also been linked to the development of candidiasis.
In HIV-positive people, oral thrush and vaginal yeast infections can occur at any time, regardless of their CD4 cell counts. The more the immune system becomes damaged, oral thrush and vaginal yeast infections are more likely to occur and recur more frequently. HIV-positive people with damaged immune systems, usually with a CD4 cell count less than 200, are also more likely to develop candidiasis deeper in their bodies, such as in their esophagus or their lungs. As with many opportunistic infections, candidiasis will usually improve or recur less often if antiretroviral therapy significantly increases CD4 cell counts.
What are the symptoms?
Symptoms of candidiasis depend on the part of the body affected. If you have any of the symptoms, you should contact your doctor:
Oral candidiasis: Some of the general symptoms of oral thrush include burning pain in the mouth or throat, altered taste (especially when eating spicy or sweet foods), and difficulty swallowing. Oral candidiasis appears as white or pinkish-red blotches on the tongue, gums, the sides or roof of the mouth, and the back of the throat. Sometimes, oral candidiasis can cause the corners of the mouth to become chapped, cracked, and sore (angular cheilitis).
Vaginal candidiasis: The most obvious symptom of vaginal yeast infections is a thick white discharge resembling cottage cheese. It can also cause itching and burning in or around the vagina, as well as a rash and tenderness of the outer lips of the vagina (the labia). HIV-positive women are more likely to experience recurrent vaginal yeast infections than HIV-negative women.
Esophageal candidiasis: This is a type of candidiasis that occurs deep down in the throat and can't always be seen by looking into the mouth. It can cause chest pain, as well as pain and difficulty when swallowing. Esophageal candidiasis is much more common in HIV-positive people with suppressed immune systems.
How is candidiasis diagnosed?
Most of the time, a doctor can diagnose candidiasis simply by looking in the mouth, at the back of the throat, or in the vagina. Sometimes it is necessary to scrape the overgrowth so that a sample can be sent to a lab.
X-rays and a special scope—called an endoscope—are used to look for candidiasis down the throat.
How is candidiasis treated?
Just as there are three different types of candidiasis, there are three somewhat different ways to treat the disease.
Treatment for Oral Candidiasis
The most common method of treating oral thrush is to use a medicated liquid that is swished around the mouth and swallowed, or a lozenge that is sucked, dissolved in the mouth, and swallowed. The treatment recommended by the U.S. Centers for Disease Control and Prevention (CDC) as the most effective and best tolerated is:
Fluconazole (Diflucan tablets): Diflucan is a tablet that must be swallowed. Studies have demonstrated that it is just as effective as clotrimazole and nystatin, but is more convenient and better tolerated. The dose is typically 100mg a day for 7 to 14 days.
Alternative treatments include:
- Clotrimazole (Mycelex trouches): These trouches, or lozenges, are used either four or five times a day for one or two weeks. Lozenges should be dissolved in the mouth slowly and should not be chewed or swallowed whole. Clotrimazole can cause stomach upset.
- Nystatin (Mycostatin liquid or pastilles): Nystatin is available in liquid and pastille (lozenge) form. The liquid dose is 5 milliliters four times a day for one or two weeks; it should be swished around the mouth slowly, for as long as possible (i.e., a few minutes), and then swallowed. One or two pastilles are taken four or five times a day for 7 to 14 days; they should be dissolved in the mouth slowly and should not be chewed or swallowed whole.
- Itraconazole (Sporanox liquid suspension): This medication is a liquid that must be swallowed. While it is as effective as the three medications listed above, it is not as well tolerated as fluconazole tablets.
- Ketoconazole (Nizoral) or itraconazole (Sporanox) capsules: These capsules, which must be swallowed, are less effective that fluconazole. However, they are alternative options if the four medications listed above cannot be used.
Another possible treatment for oral candidiasis is gentian violet (Genapax). This is a dye made from coal tar and can be purchased from some pharmacies, health food stores, and other places where complementary/alternative therapies are sold. Gentian violet is very messy and can stain clothing. It should be handled with care. For oral thrush, one of the best ways to apply the dye is by using a cotton swab. Dip the swab in the dye and coat the Candida blotches in the mouth. It is best to avoid swallowing the drug, as it can cause stomach upset. Gentian violet can also stain the inside of the mouth, but this fades over time.
Treatment for Vaginal Candidiasis
The most common method of treating vaginal yeast infections is to use a medicated cream or an insert (suppository) placed into the vagina. The most common treatments for vaginal candidiasis are available over-the-counter and can be purchased in many pharmacies. Many vaginal creams and suppositories can weaken condoms and diaphragms, which can increase the risk of pregnancy and HIV transmission.
- Clotrimazole (Gyne-Lotrimin cream): Five grams of this cream are applied every day, using a special applicator, for 7 to 14 days.
- Clotrimazole (Mycelex vaginal suppositories): Available in 100 mg and 500 mg strength suppositories and are available by prescription. The 100 mg suppositories are used every day for seven days. Alternatively, two 100 mg suppositories can be used every day for a total of three days. The 500 mg suppository is much more powerful than that 100 mg inserts and only needs to be inserted once.
- Miconazole (Monistat vaginal cream): Five grams of this cream are applied every day, using a special applicator, for seven days.
- Miconazole (Monistat vaginal suppositories): Available in 100 mg, 200 mg, and 500 mg strengths. The 100 mg and 200 mg suppositories are available over-the-counter and the 500 mg suppositories are available by prescription. The 100 mg suppositories are used once a day for seven days and the 200 mg suppositories are used once a day for three days. The 500 mg suppository only needs to be inserted once.
- Terconazole (Terazol 3 and Terazol 7 creams): Terazol 3 contains a higher dose of terconazole than Terazol 7. Terazol 7 is applied every day, using a special applicator, for seven days. Terazol 3 is applied every day for three days.
- Terconazole (Terazol 3 suppositories): These suppositories contain 80 mg terconazole and are inserted every day for three days.
- Tioconazole (Vagistat ointment): This ointment contains 300 mg tioconazole and is inserted, using a special applicator, only once.
- Butoconazole (Femstat cream): Five grams of this cream are applied every day, using a special applicator, for three days.
As with oral candidiasis, if vaginal yeast infections do not go away while using these creams of suppositories, or if the infection returns soon after treatment is stopped, more potent drugs such as nystatin (Mycostatin) liquid, itraconazole (Sporanox) liquid, or fluconazole (Diflucan) tablets can be prescribed by a doctor. Women who are pregnant should not use these oral drugs. They may harm the developing fetus.
Another possible treatment for vaginal yeast infections is gentian violet (Genapax). This is a dye made from coal tar and can be purchased from some pharmacies, health food stores, and other places where complementary/alternative therapies are sold. Genapax can be purchased in a tampon formulation; each tampon contains 5 mg of gentian violet. Gentian violet tampons can be messy and can stain clothing and undergarments. They should be handled and inserted with care. To treat vaginal yeast infections, gentian violet tampons are inserted once or twice a day for one to two weeks.
Treatment for Esophageal Candidiasis
Because esophageal candidiasis is considered to be more severe, deeper in the body, and harder to treat than either oral thrush or vaginal yeast infections, more powerful drugs—using higher doses than those used to treat oral of vaginal candidiasis—are usually needed to treat it. These drugs can cause liver enzymes to increase. They can also interact with other medications, including protease inhibitors, non-nucleoside reverse transcriptase inhibitors, as well as certain antihistamines and sedatives. Be sure to check with your doctor about other drugs you are taking before taking these antifungal treatments.
- Fluconazole (Diflucan): To treat esophageal candidiasis, an intravenous solution or 200 mg tablet of fluconazole is taken once a day for two or three weeks. Fluconasole is considered the first choice for treating esophogeal candidiasis, because blood levels of fluconazole fluctuate less than either itraconazole or ketoconazole.
- Itraconazole (Sporanox): This drug is frequently used to treat esophageal candidiasis. Many doctors are now recommending that the liquid formula (itraconazole cyclodextrin solution) be used. If the itraconazole tablets are used, they are often taken with another drug, flucytosine (Ancobon), to increase effectiveness. For oral candidiasis, the dose of itraconazole used is usually 100 mg a day for one or two weeks. For esophageal candidiasis, the dose is usually 200 mg a day for two or three weeks. Itraconazole tablets should be taken with food; itraconazole liquid should be taken on an empty stomach.
- Ketoconazole (Nizoral): 400 mg of Nizoral is taken every day for three or four weeks. This drug interacts with many antiretroviral drugs. It can increase indinavir (Crixivan), saquinavir (Invirase), and amprenavir (Agenerase) levels in the blood. Ritonavir (Norvir) can increase the amount of ketoconazole in the blood and, as a result, the daily ketoconazole dose should not exceed 200 mg.
Treatment for Severe or Drug-Resistant Candidiasis
Sometimes, candidiasis can become resistant to the "azole" drugs (all of those listed above) or is so severe that it cannot be adequately treated using any of these treatments. As a result, a drug called amphotericin B is often used. It is usually administered in a hospital through an IV line. The two types of amphotericin B are standard amphotericin B (Fungizone) and liposomal amphotericin B (Abelcet, AmBisome, Amphotec).
Amphotericin B can cause serious side effects, including kidney damage, allergic reactions (e.g., fever, chills, altered blood pressure), bone marrow damage, nausea, vomiting, and headache. The risk of kidney damage is increased if amphotericin B is combined with cidofovir (Vistide) or ganciclovir (Cytovene), two drugs used to treat CMV, and pentamidine (NebuPent), a drug used to treat PCP. The risk of bone marrow damage is increased if amphotericin B is taken at the same time as AZT (Retrovir), flucytosine (Ancobon), or ganciclovir.
Generally speaking, the liposomal amphotericin B brands are less toxic than standard amphotericin B. However, standard amphotericin B is faster acting than any of the liposomal drugs and is usually the drug of choice when candidiasis or other fungal infections are severe and an immediate threat to life.
How should pregnant women be treated for candidiasis?
Because many of the drugs used to treat fungal infections can be toxic to the developing fetus, the CDC recommends that topical treatments—such as vaginal creams or suppositories for vaginal candidiasis—be used whenever possible.
Can candidiasis be prevented?
There is no guaranteed way to prevent oral thrush, vaginal yeast infections, or the more serious forms of candidiasis from occurring. These infections are more likely to occur in HIV-positive people with compromised immune systems (less than 200 CD4 cells). Thus, one way to help prevent candidiasis from occurring is the keep the immune system healthy, such as by using antiretroviral drugs, reducing stress, eating right, and getting plenty of rest.
There is still some debate regarding the use of antifungal drugs to prevent candidiasis. There have been a few studies showing that fluconazole (Diflucan) can reduce the number of oral or vaginal fungal infections experienced by HIV-positive people with compromised immune systems. However, it may be possible that prolonged use of fluconazole—or any of the "azole" drugs—may lead to the development of drug-resistant Candida albicans. This can prevent the drugs from working correctly when they are most needed. Because of this, many doctors do not recommend that these drugs be used continuously to prevent candidiasis. However, the prolonged or continual use of antifungals may be the best option for people with a history of frequent outbreaks of oral thrush or vaginal yeast infections.
There are a number of health tips all HIV-positive people should consider to help prevent candidiasis:
- Watch your diet: It may be helpful to avoid foods high in sugar, dairy, yeast, wheat and caffeine. These types of ingredients are believed to promote fungal overgrowth.
- Eat yogurt: Many experts also recommend eating lots of yogurt that contains Lactobacillus acidophilus, a "good" bacteria believed to keep Candida albicans in check. Not all yogurt brands contain this bacteria, so be sure the packaging says "contains Lactobacillus acidophilus."
- Practice good oral hygiene: This includes brushing regularly, flossing, using an antiseptic mouthwash (e.g., Listerine), and reducing/eliminating the use of tobacco products such as chewing tobacco and cigarettes.
- For vaginal yeast infections: To help reduce the risk of vaginal infections, wear loose, natural-fiber clothing and undergarments with a cotton crotch. Also, stay away from deodorant tampons and feminine deodorant sprays.
Are there any experimental treatments?
Candidiasis is a problem for many people, regardless of whether or not they are infected with HIV. This is especially true for people who have strains of Candida that are resistant to currently available drugs. Thus, new drugs are always being developed for candidiasis and other fungal infections.
If you would like to find out if you are eligible for any clinical trials involving new treatments for candidiasis, visit ClinicalTrials.gov, a site run by the U.S. National Institutes of Health. The site has information about all HIV-related clinical studies in the United States. For more info, you can call their toll-free number at 1-800-HIV-0440 (1-800-448-0440) or email firstname.lastname@example.org.
Last Revised: January 18, 2016