Health Library
Health Library

    Boric Acid Vaginal Suppositories: Everything You Need to Know

    Updated 13 November 2020 |
    Published 24 April 2019
    Fact Checked
    Reviewed by Kate Shkodzik, MD, Obstetrician and gynecologist
    Flo Fact-Checking Standards

    Every piece of content at Flo Health adheres to the highest editorial standards for language, style, and medical accuracy. To learn what we do to deliver the best health and lifestyle insights to you, check out our content review principles.

    If your health care provider or OB-GYN has prescribed you boric acid, you may be wondering exactly what it is and how it works. Although boric acid has a long history as a treatment for a variety of medical conditions, it hasn’t been fully studied, and it’s not a common prescription in conventional medicine.

    Let’s take a closer look.

    What is boric acid? 

    Boric acid — also called hydrogen borate or boracic acid — is a weak acid that’s been used for many years as an antiseptic. The natural form of this compound is found in volcanic areas in Europe and North America and has been used at least since the time of the ancient Greeks for cleaning, preserving food, and other purposes.

    Take a quiz

    Find out what you can do with our Health Assistant

    Many of the medical applications for boric acid are connected to its use as an antiseptic, for instance, to treat minor cuts, burns, and acne. As an acid, it may also help maintain normal pH of the vagina when prescribed by a health care provider. This is why boric acid is sometimes used to treat a number of medical conditions.

    When are boric acid vaginal suppositories used?

    Boric acid suppositories are sometimes used as an alternative treatment for the following conditions:

    Boric acid suppositories for bacterial vaginosis (BV)

    Bacterial vaginosis is an infection of the vagina that is caused by excessive bacterial activity, such as gardnerella, bacteroides, and fusobacterium. Bacterial vaginosis is an imbalance between the good vaginal flora (like lactobacillus) and the bad ones. BV often comes with a white or gray vaginal discharge with a strong fishy odor. While most people do not experience any discomfort, sometimes there may be symptoms like vaginal discomfort or pain when urinating. 

    Although BV is not a sexually transmitted infection (STI), risk factors for infection include having multiple sexual partners.

    Health care providers will typically prescribe an antibiotic to treat BV, but some health care providers might recommend alternative treatments, including probiotic supplements. The effectiveness of these alternative methods is still debated among health care providers.

    Some people use boric acid capsules as an alternative treatment for bacterial vaginosis, although data on their effectiveness is limited. If you suspect you have BV, contact a health care provider for advice and treatment.

    Boric acid suppositories for yeast infections

    Vaginal yeast infections are also known as candidal vulvovaginitis or candidiasis. They result from an increased growth of yeast in the vagina, which causes irritation, swelling, and itching in the area. Other symptoms include pain and burning when urinating, thick but odorless vaginal discharge that looks like cottage cheese, and pain during sex.

    Vaginal yeast infections are associated with the candida genus of yeast, which is normally always in the vagina, just in much lower numbers. But if the balance of normal vaginal bacteria and yeast changes, symptoms of candidiasis can arise. While it’s not an STI, rates of infection tend to increase in people with multiple sexual partners. Typical treatment is an oral or topical antifungal medication.

    Boric acid suppositories are sometimes prescribed as an alternative treatment for vaginal yeast infections that keep occurring despite treatment. 

    Boric acid suppositories for trichomoniasis

    Trichomoniasis is an STI caused by the parasite trichomonas vaginalis. Typical symptoms include genital itching, a green or yellow foul-smelling vaginal discharge, and pain when urinating and during sex

    A trichomonas infection is usually treated with antibiotics, but drug resistance is an increasing problem. In some cases, boric acid suppositories might be prescribed as an alternative treatment, although their effectiveness and safety have not been fully studied.

    How to use boric acid suppositories 

    Always consult with a health care provider first.

    Boric acid suppositories are widely available without a prescription from drug stores and online retailers. A typical dose is 600 milligrams per day, but it’s crucial to consult your health care provider about the right regimen and to follow the instructions carefully.

    Here are some guidelines to follow when inserting your boric acid suppository:

    • Wash your hands thoroughly and remove the capsule from its packaging.
    • Lie back on a bed or couch with your knees bent, or stand with your knees bent.
    • Using your fingers or an applicator specifically designed for this purpose, gently insert the suppository into your vagina as far as it will comfortably go.
    • You may wish to wear a panty liner to protect your clothing from discharge from the suppository.
    • Wash your hands thoroughly afterwards.

    The suppository should be inserted at the same time each day. Many people find it convenient to insert it before going to bed

    How long does it take for boric acid suppositories to dissolve?

    Boric acid suppositories take only a few minutes to completely dissolve in the vagina. Some people prefer to wear a panty liner while using a vaginal suppository.

    How long does it take for boric acid suppositories to work?

    If you were prescribed boric acid suppositories and followed instructions from a health care provider, the symptoms may begin to improve in as little as a day. Make sure to complete the prescribed course of treatment to reduce the likelihood of the infection returning. Always consult a health care provider for advice on how much and for how long to use the suppositories.

    If you experience any discomfort or side effects, make sure to contact a health care provider right away.

    Boric acid suppositories side effects 

    Boric acid suppositories have been used for many years as an alternative treatment, but there are still not enough studies or scientific data about their safety. Boric acid suppositories can also cause side effects including:

    Stop using boric acid suppositories and seek medical advice if they cause severe discomfort.

    Here are some important restrictions to keep in mind:

    • Boric acid should not be used during pregnancy — it’s toxic to the developing fetus.
    • Boric acid causes irritation to open wounds in and around the vagina and should not be used in such cases.
    • Boric acid is highly poisonous when taken orally. It should only be used as a vaginal suppository when prescribed by a health care provider.


    “Yeast Infection (Vaginal).” Mayo Clinic, Mayo Foundation for Medical Education and Research, 16 July 2019, “Trichomoniasis - 2015 STD Treatment Guidelines.” Centers for Disease Control and Prevention, Centers for Disease Control and Prevention, 4 June 2015, Holley, Robert L., et al. “A Randomized, Double-Blind Clinical Trial of Vaginal Acidification versus Placebo for the Treatment of Symptomatic Bacterial Vaginosis.” LWW, Sexually Transmitted Disease, 4 Sept. 2003,,_Double_Blind_Clinical_Trial_of.8.aspx. Falagas, M E, et al. “Probiotics for the Treatment of Women with Bacterial Vaginosis.” Ovid, Clinical Microbiology & Infection, July 2007, Reichman, Orna, et al. “Boric Acid Addition to Suppressive Antimicrobial Therapy for Recurrent Bacterial Vaginosis.” LWW, Sexually Transmitted Diseases, Nov. 2009, Seta, F. De, et al. “Antifungal Mechanisms Supporting Boric Acid Therapy of Candida Vaginitis.” Journal of Antimicrobial Chemotherapy, vol. 63, no. 2, 2008, pp. 325–336., doi:10.1093/jac/dkn486. Xie, H, et al. “Probiotics for Vulvovaginal Candidiasis in Non-Pregnant Women.” Cochrane, 23 Nov. 2017, Boeke, A J et al. “Effect of lactic acid suppositories compared with oral metronidazole and placebo in bacterial vaginosis: a randomised clinical trial.” Genitourinary medicine vol. 69,5 (1993): 388-92. doi:10.1136/sti.69.5.388

    History of updates

    Current version (13 November 2020)

    Reviewed by Kate Shkodzik, MD, Obstetrician and gynecologist

    Published (24 April 2019)

    In this article

      Try Flo today