Antibiotics are used to kill off harmful bacteria in the body. But they can also destroy beneficial bacteria in the process, which may lead to a yeast infection.

Vaginal yeast infections are fungal infections of the vagina. They happen when a type of fungus called Candida, which occurs naturally in the vagina, begins to grow out of control. Yeast infections can cause intense itching and irritation of the vagina and vulva — the outer part of the female genital area.

Read on to learn more about why this happens and how you can reduce your risk while taking antibiotics.

Vaginas maintain their own balanced mix of yeast and bacteria. A type of bacteria called Lactobacillus keeps the vagina slightly acidic, which isn’t welcoming to yeast. This slightly acidic environment keeps yeast growing in the vagina under control.

Broad-spectrum antibiotics, which you might take for bronchitis or a sinus infection, are like a bomb to your body’s natural balance of bacteria. They wipe out the bad bacteria causing your illness. Antibiotics also wipe out beneficial bacteria, including Lactobacillus. Without enough Lactobacillus, your vagina becomes less acidic, making it an ideal environment for yeast.

There are several things you can do to reduce your risk of getting a yeast infection after you take antibiotics.

Talk to your doctor

If you have chronic yeast infections or tend to get a yeast infection every time you take antibiotics, tell your doctor. They may prescribe an oral antifungal pill called fluconazole (Diflucan) for you to take during your course of antibiotics.

You might be instructed to take one pill on the first day and another pill every seven days until you finish the antibiotics. This should help to prevent an overgrowth of yeast while taking antibiotics.

Use an over-the-counter antifungal

Using an over-the-counter (OTC) antifungal cream or suppository can help prevent yeast infections caused by antibiotics. Antifungal agents can take the place of your good bacteria, working to keep yeast in check.

Following the directions on the box, begin using your antifungal at the same time you start your antibiotics to prevent a yeast infection. You can also start using an antifungal at any point during your course of antibiotics. You can buy OTC yeast infection treatments on Amazon.

Replenish your good bacteria

Antibiotics attack good bacteria all over your body. You may be able to undo some of this damage by increasing the numbers of good bacteria in your body.

Consider taking a probiotic supplement containing Lactobacillus, like this one, available on Amazon. You can also try adding some yogurt containing live active cultures to your diet. Here’s a guide to brands containing Lactobacillus acidophilus.

Use yogurt

While eating yogurt can help to replenish good bacteria, applying it near your vagina may also offer a little help. Just make sure you choose one that’s unflavored and contains live active cultures. Apply it to your vulva for itch relief. You can also use a tampon applicator to put it inside your vagina.

Learn more about how to use yogurt for a yeast infection.

Don’t use antibiotics unnecessarily

Try to avoid using antibiotics for minor infections, such as an ear infection. In these cases, antibiotics will only shorten your healing time by a day or two. Ask your doctor if there’s anything else that might help before starting antibiotics.

But if your doctor does recommend taking them, make sure to finish the entire course. Not doing so can contribute to antibiotic resistance, which makes antibiotics ineffective against harmful bacteria.

Other tips for prevention

Follow these tips to reduce your risk of developing a yeast infection, regardless of whether you’re taking antiobitoics:

  • Change out of wet bathing suits and underwear as soon as possible. Yeast thrives in moist environments.
  • Avoid hot tubs and very hot baths. The only thing yeast loves more than a moist environment is a warm one.
  • Wear loose-fitting clothing. While there’s no clear link between tight clothing and yeast infections, tight pants can increase heat and moisture around your vulva.
  • Wear breathable, cotton underwear. Even a cotton crotch will help keep things cool and dry.
  • Never douche. Douching removes healthy bacteria.
  • Avoid vaginal deodorant products. This includes sprays, powders, and scented pads and tampons.
  • If you have diabetes, keep your blood sugar under control. High blood sugar levels encourage yeast growth.

If your yeast infection doesn’t improve after treatment, you should consult your doctor. Over-the-counter antifungal creams can take up to 10 days to treat a yeast infection.

You should make an appointment if you get recurrent yeast infections, which refers to having four or more yeast infections a year. These usually require prescription treatment because yogurt and other home remedies aren’t effective for this type of yeast infection.

If you’re still having symptoms after this point, you could have a different condition, such as bacterial vaginosis. This is a bacterial infection with symptoms very similar to those of a yeast infection. But because it’s not caused by a fungus, it won’t respond to antifungal treatments.

Antibiotics can cause yeast infections in some people because they kill off beneficial bacteria that prevent the overgrowth of yeast in the vagina. But there are several things you can do to offset the negative effects of antibiotics and reduce your risk of developing a yeast infection.

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