DEAR MAYO CLINIC: What is the difference between bacterial vaginosis and a yeast infection? I’ve had painful itching for two weeks but have not been to see a doctor yet. Are over-the-counter medications effective in treating both?
ANSWER: Bacterial vaginosis, or BV, and vaginal yeast infections may have some symptoms that seem similar, but they have different causes and require different treatment. Over-the-counter remedies are available for a yeast infection. BV typically requires prescription medication. See your doctor to get an accurate diagnosis. Then he or she can help you decide on the best treatment.
BV and yeast infections both fall under the broad category of vaginal infections, called vaginitis. These infections are quite common in women. They usually can be treated effectively without any long-term problems. You need to know which type of infection you have, however, to make sure you get the right treatment.
BV is the result of an overgrowth of one of several organisms normally present in your vagina. Usually, the “good” bacteria, called lactobacilli, outnumber the “bad” bacteria, called anaerobes. If anaerobic bacteria become too numerous, they upset the natural balance of microorganisms in your vagina, resulting in bacterial vaginosis.
One of the most common reasons for an overgrowth of anaerobic bacteria is douching — rinsing out your vagina with water or a cleansing agent. In most cases, douching is not recommended because it disrupts the vaginal environment and can lead to BV, as well as other types of vaginitis, including a vaginal yeast infection.
In contrast to BV, a vaginal yeast infection is caused by a fungus called candida. Candida is a microorganism that’s normally present in your vagina. Your vagina naturally contains a balanced mix of yeast and bacteria. Lactobacillus bacteria produce acid, which discourages overgrowth of yeast in the vagina. But disruption of the balance between the two can result in an overgrowth of yeast.
A number of factors can result in an overgrowth of vaginal yeast. You may be at higher risk for a yeast infection if you take antibiotics regularly. Antibiotic use can cause a decrease in the amount of lactobacillus bacteria in your vagina, allowing yeast to overgrow. Women who take birth control pills containing estrogen, who are pregnant, who have uncontrolled diabetes, or whose immune systems are weakened are also at an increased risk for yeast infections.
Symptoms of BV and a yeast infection both usually include vaginal discharge. BV typically causes discharge that’s thin and gray or yellow. A yeast infection causes discharge that is thick and white, with a cottage-cheese type appearance. BV is associated with a foul, “fishy” vaginal odor, while most women don’t notice an odor with a yeast infection. A yeast infection also typically causes itching, particularly in younger women, and may include a burning sensation, especially during urination. In general, BV doesn’t cause itching or burning.
You can treat a yeast infection with over-the-counter medication. But if you aren’t sure if that’s what is causing your symptoms, see your doctor first. To make a diagnosis, your doctor likely will perform a pelvic exam and take a sample of vaginal secretions to be examined under a microscope.
Prescription medications such as metronidazole, clindamycin and tinidazole often can effectively treat BV. For yeast infections, antifungal creams, ointments, tablets or suppositories usually are all that’s needed to restore the vaginal balance of bacteria and yeast and eliminate symptoms. If a yeast infection is causing severe symptoms, or if the infection comes back multiple times, additional treatment may be necessary to keep the yeast in check.
If your symptoms don’t improve with treatment, it’s important to contact your doctor. It’s possible that a yeast infection or BV may not be the problem, and further evaluation is needed. — Mary Marnach, M.D., Obstetrics & Gynecology, Mayo Clinic, Rochester, Minn.