What Is a Yeast Infection? Symptoms, Causes, Diagnosis, Treatment, and Prevention

A vaginal yeast infection is an infection resulting from the overgrowth of yeast — a type of fungus — of the genus candida.

Also called candidal vaginitis, vaginal candidiasis, or vulvovaginal candidiasis, yeast infections are most commonly caused by Candida albicans.

It is easily treated with antifungal medication. If symptoms persist for more than a week, check with your doctor to rule out a more serious condition. (1,2)

The most common symptoms of mild vaginal yeast infections include:

• Vaginal itching
• Vaginal soreness
• Pain or discomfort during intercourse or when urinating
• Vaginal discharge that is clumpy (like cottage cheese), possibly smelling like yeast or bread
• Vaginal discharge that is watery

More severe infections can cause redness, swelling, and cracks in the skin outside the vagina (the vulva). (1,2,3,4)

Fungi of the genus candida normally live on the skin and inside the body (mouth, throat, gut, and vagina) without causing health problems. Research suggests about 20 percent of women have candida in the vagina that doesn’t cause infection. (1)

There are many species of candida, at least 15 of which are known to cause infections if they multiply out of control. (5)

In the United States, around 90 percent of vaginal yeast infections are caused by the species C. albicans. Most other cases are caused by C. glabrata. Less frequently, C. parapsilosis, C. tropicalis, and C. krusei cause vaginal yeast infections. (6,7)

Candida yeast cause an infection when something throws off the balance of microorganisms that live in and on your body, such as:

• Pregnancy
• Certain types of medication, including hormonal contraceptives (birth control pills, patches, or vaginal rings), antibiotics, and steroids
• Immune-suppressing diseases, including HIV
• Diabetes
• Stress and lack of sleep, which can weaken the immune system (2,3)

Additionally, certain lifestyle habits may also promote the growth of candida, including:

• Being sexually active (vaginal yeast infections are not considered a sexually transmitted infection, but they are more common in women who are sexually active)
• Eating a diet high in sugar (a yeast food source)
• Douching
• Other contraceptive use, including vaginal sponges, diaphragms, and intrauterine devices (IUDs)
• Maintaining poor vaginal hygiene

Wearing clothing that keeps the vaginal area warm and moist, such as synthetic underwear, pajama bottoms, and tight jeans or spandex (3,8,9)

Though it may be tempting to self-diagnose a vaginal yeast infection, since effective over-the-counter (OTC) treatments exist, experts recommend you see a doctor.

Several other conditions — notably bacterial vaginosis (vaginal infection caused by bacteria), trichomoniasis (a sexually transmitted infection), and dermatitis (irritated skin) — can cause symptoms similar to yeast infections, making self-diagnosis difficult. (3) In one 2002 study, only about 34 percent of women who purchased OTC antifungal medications accurately diagnosed themselves with a yeast infection.

You should especially see a doctor if:

• This is your first yeast infection.
• Medications for a previous yeast infection are not working on your current infection.
• Your symptoms differ from previous yeast infections. (10)

To diagnose a yeast infection, your doctor will ask you about your symptoms and medical history, perform a pelvic exam, and take a sample of vaginal discharge. A lab technician will examine the discharge to determine if there is an overgrowth of candida.

Your doctor will make a diagnosis based on all the findings — a positive fungal culture alone does not mean you have a yeast infection because women can have candida in their vagina without showing symptoms. (1,3) Some clinicians can also make a diagnosis by looking at a discharge sample under a microscope, although a bacteria culture is the gold standard.

Most yeast infections clear up within a few days, depending on the severity of the infection and the medication used.

But up to 8 percent of women develop recurrent or chronic yeast infections (at least four infections per year). These infections are typically due to non-albicans species and may require different treatment. (3,7)

Vaginal yeast infections are treated with over-the-counter or prescription antifungal creams, ointments, tablets, suppositories, or oral medications. You will need to take the medication for 1 to 7 days, depending on which medication you are using.

Medications Options

OTC and prescription drugs that may be used include:

• miconazole (Monistat)
• clotrimazole
• tioconazole
• butoconazole (Gynazole)
  
• terconazole (Terazol)
• fluconazole (Diflucan), a prescription single-dose pill
• Boric acid (suppository gelatin capsules recommended for non-albicans species)

If you have recurrent yeast infections, you may require multiple doses of fluconazole in the first week of infection, followed by at least six months of maintenance therapy (periodic fluconazole doses depending on the presence of symptoms). (11,12,13)

Alternative and Complementary Therapies

Can home remedies and natural cures help treat and prevent vaginal yeast infections? Many women wonder what else they can do to deal with yeast problems. Outside over-the-counter products and prescription medication for vaginal yeast infections, some women choose to treat their ailments with natural or home remedies.

Home remedies for vaginal yeast infections include:

• Probiotics (oral and intravaginal)
• Vinegar (vaginal irrigation)
• Povidone-iodine (topical solution, ointments, and vaginal suppositories)
• Garlic pills
• Tea tree oil (topical)
• Propolis (vaginal cream)
• Sodium bicarbonate (bath or vaginal irrigation)
• Dietary changes to reduce sugar intake, including from dairy products (13)

While they are very popular, the effectiveness of home remedies for treating and preventing yeast infections is not very well known or understood.

Some remedies, at least, appear to be helpful for vaginal yeast infections, though more research is needed. For example, using probiotics as an adjuvant therapy could help cure yeast infections, but the quality of evidence is low or very low, according to a 2017 review. (14)

Changing one’s diet or reducing one’s sugar intake can be important for patients whose infection is linked to poorly controlled diabetes.

Can You Have Sex While You Have a Vaginal Yeast Infection?

Yeast infections are not considered sexually transmitted infections (STIs), as most are not transmitted person to person and they can occur in people who have never had sex. But having sex with a vaginal yeast infection can be, well, complicated.

There are a number of reasons you may want to wait until your infection clears to have sex:

• Vaginal penetration may interfere with yeast infection treatment.
• It might further irritate your vagina.
• The yeast infection medication might damage condoms.
• You can pass on the fungi to your partner (15 percent of men get an itchy rash on their penis if they have unprotected sex with a woman with a yeast infection). (15,16)

Prevention of a Yeast Infection

While the infections are not dangerous, they are uncomfortable and annoying enough that women may want to help prevent them. Risk-reducing steps include: (17)

• Practice good hygiene.
• Wear looser clothing in breathable fabrics.
• Avoid scented sprays and bath products.
• Don’t douche.
• Avoid certain medications (when possible).
• Maintain proper diet, sleep, and exercise.
• Keep the area around the vagina clean and dry.

As many as 75 percent of women will get a vaginal yeast infection at least once in their lives. And 50 percent of these women will experience more than one infection. (17) As many as 8 percent of women experience recurrent or chronic yeast infections, with four or more infections in a single year. (3,7)

Vaginal yeast infection is the second most common type of vaginal infection, after bacterial vaginal infection, in the United States. It results in 1.4 million outpatient visits a year. (1,17)

Vulvovaginal Candidiasis and Pregnancy

Candida yeast colonizes the vagina of at least 20 percent of all women — and 30 percent of all pregnant women.

Research suggests that vulvovaginal candidiasis is especially common among pregnant women.

Both the increased candida colonization and yeast infection rates during pregnancy appear to be caused by several pregnancy-related factors, including increased estrogen levels, reduced immunity, and increased concentrations of sugar (a food source for yeast) in vaginal secretions. (18)

The symptoms and severity of yeast infections are no different during pregnancy, but treatment varies slightly.

Applying a topical azole for seven days is the recommended treatment for yeast infections during pregnancy; oral azoles have not been proven safe for pregnant women.

In fact, research published in 2016 suggests oral azoles increase a pregnant woman’s risk of spontaneous abortion. (19)

Diabetes and Vaginal Yeast Infections

Vaginal yeast infections are also considered a complication of type 2 diabetes, as the metabolic disease makes you more susceptible to the infection.

Diabetes mellitus also makes you more prone to infections by the azole-resistant species of yeast C. glabrata.

If your diabetes is uncontrolled, you’ll have high levels of sugar in your blood, which also affects the levels of sugar in other areas of your body. Specifically, the mucous membrane in the vagina and vulva becomes saturated with sugar, allowing candida to rapidly reproduce.

A diet high in refined sugars may contribute to a diabetic woman’s risk of yeast infection. (6)

Nongenital Yeast Infections

Though the term “yeast infection” is most often used to refer to a vaginal infection, it also applies to other types of candidiasis.

A yeast infection of the mouth and throat is called thrush, or oropharyngeal candidiasis. (20)

When a yeast infection affects the esophagus (tube connecting the throat and stomach), it’s called esophageal candidiasis, or candida esophagitis. (5)

A yeast infection of the skin — which typically occurs in warm, moist areas, such as the armpits and groin — is called cutaneous candidiasis. (21)

And if candida gets into the bloodstream, such as from using a contaminated intravenous catheter or as a complication of thrush, the yeast can cause a deadly infection called invasive candidiasis. Here, it enters your bloodstream and travels to other parts of your body, including your lungs, liver, and heart valves.

It can cause infection or inflammation in various body parts, such as meningitis (infection of the membranes of the brain), esophagitis (esophagus), endophthalmitis (eyes), endocarditis (heart), urinary tract infections (UTIs), and arthritis (joints). (7,22)

Candida can cause an infection of the bloodstream itself, called candidemia. (23)

Invasive candidiasis most frequently affects people who are critically ill and in intensive care units, such as from yeast that travels to the bloodstream from the gut, or leakage after abdominal surgery. (24)

Additionally, men can get yeast infections in their genitals (candidal balanitis), mouths, and other areas.

For more go-tos on preventing, diagnosing, and, of course, treating yeast infections, here are some additional sources of information that can help.

Mayo Clinic

The Mayo Clinic is a well-respected, integrated clinical practice, education, and research institution that prides itself on offering the most up-to-date medical information to the public. On this website users can readily access an easy-to-digest overview of yeast infections, but one of our favorite features is the “preparing for your appointment” section, which highlights questions patients will want to ask their healthcare provider during the diagnosis and treatment process.

MedlinePlus

MedlinePlus is the patient-centered offshoot of the U.S. National Library of Medicine, and offers need-to-know basics of yeast infections. But it’s also a thorough clearinghouse for the latest yeast infection clinical trials and published journal articles. We also love that the site breaks down yeast infection information by patient type, including children, teens, and men.

Office on Women’s Health

OWH is a part of the U.S. Department of Health and Human Services created to address critical health issues that affect women, making this an excellent source for yeast infection information. The fact sheet filled with frequently asked questions is especially helpful, as is their “Find a Health Center” widget.

Healthy Children

Powered by the pediatricians behind the American Academy of Pediatrics, the yeast infection section of their website highlights all the essential info needed on the hows and whys of yeast infections in girls and young women. We appreciate that the site also has solid info on other candida infections that children and teens can experience, complete with a symptom checker chart.

Centers for Disease Control and Prevention (CDC)

The CDC has thorough and up-to-date info on all things related to vaginal candidiasis (aka vaginal yeast infections) and candida infections of the mouth, throat, and esophagus. But you don’t have to keep clicking to stay in the know. Instead, there’s a “get email updates” option where you can enter your contact info to automatically receive updated information on yeast infections (or any health topics of interest) directly to your inbox.