What’s the Deal with Using Boric Acid to Treat Yeast Infections?

A friend once described a yeast infection to me as “the urge to shove a hairbrush in your vagina just to get to what itches” which is probably the most profound and accurate depiction I've ever heard. (To clarify: Definitely do not do this.) And the only thing worse than a yeast infection is a yeast infection that either won't go away or just keeps coming back. 

If you've tried over-the-counter yeast infection treatments or even prescription treatments and still can't get relief, you might have come across boric acid as a suggested solution. Maybe a health care provider recommended it to you once, or maybe you saw it advertised on Instagram or a wellness site as a “clean” way to kill yeast and balance your delicate vaginal flora. 

So what exactly is boric acid? And why isn't it a first-line treatment for our raging yeast infections? We dug through the research and spoke with board-certified gynecologists about this intriguing option so you can make an informed decision about how to treat your yeast infections. 

Yeast infections, formally known as vaginal candidiasis, are vaginal infections caused by an overgrowth of yeast, which is a type of fungus. They're tragically common: The CDC estimates that 75 percent of people with vaginas will have at least one yeast infection, while 40–45 percent will have more than one. The vast majority of yeast infections are caused by an overgrowth of Candida albicans, but some are caused by other species, like Candida glabrata. Most of the time you won't know what pathogen is behind all this chaos, you'll just want it gone. 

According to the CDC, symptoms of yeast infections usually include: 

• Itching and discomfort around your vagina and vulva 
• Burning or pain—particularly when you pee or have sex 
• Redness or swelling around your vulva 
• Thick, white, odorless vaginal discharge (think: cottage cheese) or a watery discharge that's different than your usual 

(As you've probably noticed, yeast infection symptoms are similar to so many other vaginal infections and conditions, namely bacterial vaginosis [BV], so it's worth getting an actual diagnosis to make sure you're treating the right thing.) 

Understanding why yeast infections happen in the first place is crucial to getting relief. “You need some yeast and some bacteria to live in harmony in your vagina,” board-certified OB-GYN Shieva Ghofrany, co-founder of Tribe Called V, told VICE. Yeast infections happen when this balance of yeast and bacteria is thrown out of whack, which can be caused by so many things, like taking antibiotics, having sex, experiencing hormonal fluctuations (like from pregnancy or birth control), douching, or even staying in tight, sweaty yoga pants for too long.   

The constellation of factors that triggers a yeast infection in one vagina may not necessarily bother the next one, so keeping a log of when your symptoms start and what might be behind them can be helpful. For instance, if you get a yeast infection every time you have sex without a condom, it might be that semen is throwing off your vaginal balance. Or if you always seem to get yeast infections the week before your period, that's something worth telling your provider, too. 

Because yeast infections are caused by the overgrowth of a type of fungus, they're typically treated with antifungal medications called azoles (like fluconazole and miconazole). You can find over-the-counter antifungal creams that go in the vagina, or your provider can write you a prescription for a cream or an oral pill. 

That all sounds easy enough... but sometimes a yeast infection won't respond to those antifungals, or it might clear up and then come right back. There are a few reasons why that might happen. In some cases, the infection could be caused by a type of yeast that's more resistant to those azole medications. Or perhaps the conditions that triggered your last yeast infection are still happening—whether that's hormonal fluctuations from your menstrual cycle or a wardrobe that's mostly spandex. Or maybe your symptoms are caused by something else entirely—another vaginal infection or vulvar condition that just happens to exist alongside that yeast infection you just treated. 

Whatever the case may be, it's frustrating. And it's not surprising that you'd lose faith in the process and go searching for alternative treatments. Enter: boric acid. 

Boric acid is a naturally occurring compound consisting of oxygen, boron, and hydrogen. When it comes to treating yeast infections, boric acid is put in a gel cap suppository that gets inserted in the vagina. (It's also quite a powerful roach killer.) 

While this might sound like a substance that doesn't belong anywhere near your vagina, it's actually safe and even recommended under very specific circumstances. “There is an indication for boric acid used for yeast infections,” board-certified gynecologist Staci Tanouye told VICE. “But it is specifically for recurrent yeast or yeast that's resistant to other traditional treatments.” The CDC echoes this very limited recommendation. 

Exactly how boric acid works isn't clear, but there are a few theories. For starters, boric acid is an astringent, which means it's very drying. “It can disrupt the normal vaginal microbiome for that reason. And we think because it's disruptive to that, then it can disturb the yeast or work against the yeast,” explained Tanouye. 

Another popular theory is that boric acid may be acidifying the vagina in a way that helps it regain the proper balance of yeast and bacteria. But this theory is often disputed by the fact that boric acid is actually a weak acid. “It's probably not a strong enough acid to actually work specifically in that way to alter pH,” said Tanouye. “Maybe that's contributing a little bit, but it's probably not the main mechanism based on how it works.” 

A study published in 2009 in the Journal of Antimicrobial Chemotherapy examined the antifungal properties of boric acid against yeast in a lab and found that it was both fungistatic (meaning it limits the growth of fungus) and fungicidal (meaning it actually kills fungus). The researchers also aptly noted: “It is surprising that so little is known about a compound that is so commonly used.” 

So, why not just use boric acid all the time? Well, it's important to note that boric acid doesn't just kill yeast—it can disrupt the entire vaginal microbiome. That may sound a bit like a scorched Earth approach, but Tanouye explained this can be particularly helpful in dealing with chronic yeast infections. “We're using it to disrupt the whole system so we can get in and try to maintain low levels of yeast if we're dealing with chronic yeast.”

As you can imagine, this total disruption strategy isn't recommended as a first-line treatment for your run-of-the-mill yeast infection, and it isn't something you want to try whenever you feel any odd vagina symptom. 

“Boric acid, I believe, does have a role, but it has to be used appropriately and judiciously—and with a conversation,” said Ghofrany. 

The fact that boric acid is “naturally occurring”—as opposed to, say, a prescription like fluconazole—makes it attractive to some people, and marketers are well aware of that fact. A quick Google search will deliver several boric acid suppositories in cute, pastel packaging. Their marketing emphasizes “clean ingredients,” “plant-based” care, and “one holistic ingredient.” But it's important to remember that “natural" does not equal “harmless”—or something that naturally belongs in your vagina, for that matter. (Arsenic, for example, is also natural and plant-based, but you shouldn’t ever put that in your vagina.) 

“I do believe that we don't always have to use only Western medication,” said Ghofrany, who clarified that she is a Western medical doctor who also studies more integrative or Eastern modalities. “But if you are a believer in these alternatives then you have to accept that they will potentially come with side effects just like Western medications.” 

On that note: You should never, ever swallow boric acid, as it can be toxic. It's also not recommended for people who are pregnant, and it can be very irritating to people with vulvar skin conditions or those who are menopausal and already dealing with vaginal dryness, warned Tanouye.  

“This is marketed as that product that is not a medication, it's not an antibiotic, it's not an antifungal, and so it's going to be somehow better for you or more gentle for you or less irritating for you. And really it's not always the case,” said Tanouye. “It's purely smart marketing on their part. But it does make for a very confusing environment for the consumer.”

“I don't think it's wrong for people to buy it over-the-counter," said Ghofrany. “I think it's wrong that these over-the-counter companies are—for the purpose of profit—implying that their product will be harmless and effective all at the same time, which is not true.”  

No one would argue with the fact that it is easier to order a bottle of boric acid suppositories online than it is to find medical care, lab tests, and prescriptions for vaginal discomfort—not to mention pay for all of that. But there are some very good reasons why you should try to get a diagnosis before you start throwing possible solutions at your vagina. 

For starters, you might not even have a yeast infection. “There are studies that show we are actually really bad at self-diagnosis,” noted Tanouye. “Even people who have had yeast infections before—although they're a little bit better at self-diagnosis—it's still not good.” 

This isn't your fault—yeast infection symptoms are notoriously non-specific, so it's not uncommon to mistake other conditions for a yeast infection. But if you try to treat with boric acid—or even an over-the-counter antifungal cream—and it's not actually a yeast infection, you'll most likely end up throwing off your vaginal microbiome even more. This imbalance and irritation can make you more vulnerable to other opportunistic infections, like STIs, explained Ghofrany. Not only that, but you may be delaying the diagnosis and treatment of something more serious by trying to troubleshoot at home. 

“I always say if you have burning, itching, or an odor, you should see the doctor or practitioner,” said Ghofrany. That said, there may be a situation where you and your provider have evaluated your symptoms and triggers, you've tried a few different treatments, and you've decided that boric acid is an integral part of managing your yeast infections. 

“I think it can be something that you ultimately self-treat, but only after an evaluation,” said Ghofrany. 

If you do decide (with your provider!) to use boric acid, you can typically find it online, at the drugstore, or at a compounding pharmacy (where you'll need a prescription for it). If you're opting for over-the-counter, Tanouye suggested going “with a company that maybe has a little bit more at stake in terms of reputation” rather than some brand new company that just popped up in your Instagram ads. 

Before speaking with Ghofrany and Tanouye, I had no idea how many factors were involved in diagnosing and treating yeast infections. 

“Sometimes I do feel like that annoying doctor that's like, ‘No, I need you to come in so I can confirm that it is what you think it is,’” said Tanouye. “And in the end it is what you think it is, and I'm giving you the treatment that you probably could have just done over the counter easily on your own. So the whole thing seems annoying. But at the same time, what if it wasn't?”  

And, unfortunately, at the end of all that your yeast infection may soldier on—perhaps because of a trigger you and your doctor haven't pinpointed yet, or maybe because this yeast is resistant to the medication you tried (something you would only know if you got a culture test, which Ghofrany and Tanouye said often isn't used until after the first treatment fails because they can be hundreds of dollars and often aren't covered by insurance, naturally). 

“It really does just suck,” Tanouye empathized. 

There is no one-size-fits-all yeast infection treatment. In fact, just this summer the FDA approved a new type of antifungal to treat yeast infections that is expected to be available later in 2021 and may be helpful in treating resistant cases. 

So, if you're struggling with yeast infection after yeast infection, try to see a health care provider for help. If they don't explain why they're recommending a particular treatment or why they're ordering (or not ordering) a particular test, ask for clarification and for options. Remember that you are an informed consumer in this situation and that if you aren't feeling heard or respected, you are free to go elsewhere. 

Figuring out the best treatment method for you will probably always involve a detailed discussion of your symptoms, your triggers, your experience with previous treatment options, and your preference for pills versus creams. Feel free to bring up boric acid as part of that discussion. As the experts explained, boric acid is a valuable tool in fighting yeast infections—it's just not exactly the vaginal Swiss army knife it's made out to be in Instagram ads. 

Casey Gueren is the author of It's Probably Nothing: The Stress-Less Guide to Dealing with Health Anxiety, Wellness Fads, and Overhyped Headlines, coming September 2021.