Boric acid is a white, crystalline chemical substance that has antifungal and antiviral properties. It is used in various prescription pharmaceutical products and is also available without a prescription. Some experts now recommend vaginal boric acid capsules as a treatment option for vaginal yeast infections, particularly infections that can't be cured by antifungal yeast infection medicines.footnote 1
If you are pregnant, do not use vaginal boric acid treatment.
How do I use boric acid?
You can make your own boric acid suppositories by filling size 0 gelatin capsules with boric acid. The amount of boric acid needed and how long you use it depends on the type of infection you have.footnote 1
- Standard yeast infections. Try using an antifungal cream or suppository cream first.
- Recurrent yeast infections. Use a 300 mg to 600 mg capsule once a day for 14 days. To help keep the infection from coming back use a 300 mg capsule for 5 days each month beginning the first day of the menstrual cycle for at least six months. After six months stop using the boric acid. If you get another vaginal yeast infection see your doctor.
- Non-albicans vaginal yeast infections. If your doctor tells you that you have a non-albicans vaginal yeast infection, use a 600 mg capsule once a day for 14 days. If your symptoms come back, see your doctor.
You may find it easier to use boric acid capsules at bedtime.
Is it effective?
More research is needed to find out how well boric acid works. Some studies have shown it cures up to 70 out of 100 women. Symptoms return in some women. Check with your doctor to see if you need to continue using boric acid over several months to relieve your symptoms.footnote 1
Is it safe?
When used in capsules as a vaginal suppository, boric acid is only known to sometimes cause skin irritation. But when used by mouth (internally), on open wounds, or by children, boric acid is toxic. Keep boric acid out of the reach of children. Boric acid is not safe to use if you are pregnant.
- Expert Working Group on Canadian Guidelines for Sexually Transmitted Infections (2013). Canadian guidelines on sexually transmitted infections: Section 4—Management and treatment of specific syndromes. Public Health Agency of Canada. http://www.phac-aspc.gc.ca/std-mts/sti-its/cgsti-ldcits/section-4-8-eng.php. Accessed May 22, 2015.
Other Works Consulted
- Expert Working Group on Canadian Guidelines for Sexually Transmitted Infections (2014). Canadian guidelines on sexually transmitted infections: Supplementary statement for recommendations related to the diagnosis, management, and follow-up of vaginal discharge. Public Health Agency of Canada. http://www.phac-aspc.gc.ca/std-mts/sti-its/cgsti-ldcits/disc-pert-eng.php. Accessed May 22, 2015.
Current as of: July 17, 2020
Author: Healthwise Staff
Kathleen Romito MD - Family Medicine
Anne C. Poinier MD - Internal Medicine
Adam Husney MD - Family Medicine
Martin J. Gabica MD - Family Medicine
Deborah A. Penava BA, MD, FRCSC, MPH - Obstetrics and Gynecology
Current as of: July 17, 2020