Raise your hand (or, erm, maybe don’t) if you’ve ever gotten a ripe whiff of your armpits in the middle of the day and wondered, what the hell is going on under there? Well, you can likely blame your deodorant not working. That’s right—dermatologists say it’s fully possible for your favorite old-faithful D.O. to betray you, even after years of use.

If that makes you feel personally victimized by the tube of antiperspirant sitting on your bathroom counter, it’s time to get down to business and figure out exactly what shattered the unbreakable bond you once shared. Keep reading for dermatologist insights on what’s messing with your deodorant’s effectiveness and exactly how to make your pits smell fresh again.

Deodorant vs. antiperspirant: What’s the difference and what makes them work?

In order to understand why your deodorant isn’t working, it’s important to understand why your armpits smell in the first place. Contrary to popular belief, it’s actually not solely because of your sweat. Instead, it’s because of how your sweat interacts with the bacteria living on the surface of your skin, which can release an odor.

Antiperspirant and deodorant help combat that odor. While the two terms are often used interchangeably, they work in two very different ways. Antiperspirants—a category that some, but not all, deodorants fall into—use an active ingredient (usually aluminum) to plug up the sweat glands. This provides sweat control, stopping sweat from making it up to the surface (and keeping your favorite shirts dry). This also prevents any smelliness, as wet underarms are a breeding ground for odor-causing bacteria.

Pure deodorants, on the other hand, don’t have the same ability to plug up the sweat glands. Instead, they work to mask odor with fragrance and alcohol, which acidifies the sweat and makes it a less hospitable place for bacteria to live. “Deodorants may also contain ingredients that, although they may help to absorb moisture, are not truly blocking or decreasing the release of sweat,” says Marisa Garshick, MD, FAAD, a board-certified dermatologist in New York City.

The TL;DR? “Antiperspirants refer to products that are designed to block the release of sweat, while deodorants are designed to mask odor and may also work to absorb excess moisture,” says Dr. Garshick. When either type of product is working properly, the result is a reduction in body odor. So if you’re left wondering, why is my deodorant not working all of a sudden?, it may not technically be due to your deodorant choices.

Why is my deodorant not working all of a sudden?

You’re experiencing a major deodorant failure—and it’s not because you forgot to put on deodorant. So why has your deodorant’s effectiveness (be it in preventing underarm odor or sweat control) gone down the drain? According to the experts, it could be less to do with the trusty deodorant you’ve been using and more to do with other factors you have less control over.

“Perceived differences in smell may have to do with how much the person is actually sweating,” says Morgan Rabach, MD, board-certified dermatologist and the founder of LM Medical. Things like stress, hormonal changes, new medications, and different lifestyle factors (like harder workouts or shifts in the weather) can all impact how you sweat, and your go-to deodorant may not be able to stand up to the new situation. “There also can be changes in the natural bacterial flora that live on the skin, [as in] increased amounts, that lead to more bacteria interacting with the sweat and making the odor,” she adds.

Another common deodorant issue is too much product buildup under your armpits, which can lead to a lack of effectiveness. “Deodorants coat the underarm skin, layering a film on the armpit, and the residue stays on even after normal bathing,” says Alicia Zalka, MD, board-certified dermatologist and founder of Surface Deep Anti-Odorant. If you’re using an antiperspirant, this could cause your skin to lose its response to the active ingredient (typically aluminum) that’s traditionally been able to keep sweat at bay. “When that happens, the sweat gland and its sweat duct will return to its normal function of delivering sweat to the surface of the skin,” she says.

Finally, menopause—which women generally experience in their 40s and 50s—could cause deodorant to stop working as effectively, too. While there are many surprising menopause symptoms to be aware of, a change in underarm odor is one of them. “Bacteria metabolize sweat to create distinctive odors, and so after menopause, bacteria change on the skin, and these different bacteria can lead to different scents being produced,” Felice Gersh, MD, board-certified OB/GYN and founder of the Integrative Medical Group of Irvine, previously told Well+Good.

What to do when your deodorant doesn’t work

Whether you’re dealing with underarm odor or a lack of sweat control, your deodorant clearly isn’t doing its job anymore. With that, it’s time to bring in some dermatologist insights so you can get your personal hygiene routine back on track.

1. Go deodorant-free for a few days

In order to fix the situation, Dr. Zalka first suggests pressing the “reset” button on your deodorant routine. Stop using deodorant on your armpits for three or four days to allow them to return to their natural state, then test your go-to product again. If you’re still experiencing sweat or body odor concerns after starting it again, it may be time to test out other deodorant choices.

Try a natural deodorant if you’ve been using an aluminum-based antiperspirant. Or opt for magnesium deodorant. Experts say it’s a less irritating ingredient than baking soda, which is used in most natural options. No matter your age, you could also give the best deodorants for teens a try, which tend to utilize safe, effective, and gentle ingredients.

2. Use an antibacterial wash

There are other ways to stop armpits from smelling beyond using deodorant. If you’re experiencing deodorant failure, try using an antibacterial wash in the shower. Particularly one that incorporates benzoyl peroxide into the mix, which reduces odor-causing bacteria. “The bacteria and sweat on the skin interact to create body odor, so reducing sweat, bacteria, or both is the best way to combat body odor,” Caren Campbell, MD, a board-certified dermatologist based in San Francisco, previously told Well+Good.

If menopause caused your deodorant to stop working, Dr. Gersh says this method could be a great option. She recommends melting your antiperspirant troubles away by using a gentle body wash that contains gentle shea butter and soothing essential oils.

3. Try glycolic acid

If deodorant isn’t doing the trick, Dr. Zalka recommends swiping a glycolic acid product onto your armpits. “It creates a more acidic skin environment to offset the alkaline pH often caused by soaps, which makes it inhospitable for bacteria related to odor-causing skin flora to take hold,” she previously told Well+Good. “It also reduces sebum oil deposits on the armpit skin, which further reduces the odor process, and works as a gentle exfoliator to remove dead skin cells and other clogging elements.”

4. Spritz on a natural fragrance

Another thing you can do if no deodorant works for you is spray on your best-smelling fragrance. Sure, this might not be the greatest option on a hot day or for a sweaty workout when your body odor concerns are at their peak. But if you pair a natural perfume with some of these other methods—like antibacterial washes or glycolic acid—you can keep your B.O. in check.

How to apply antiperspirant correctly

Your deodorant’s effectiveness could come down to the application. When you’re swiping on antiperspirant, Dr. Garshick says there are two things to keep in mind: how you’re applying it and when you’re applying it.

Start by getting rid of any old deodorant buildup under your armpits before applying new antiperspirant, which can prevent it from properly doing its job. Then to up its effectiveness—and minimize any deodorant issues like irritation—Dr. Garshick says to only apply antiperspirant once your skin is completely dry. When all moisture is gone, apply a couple strokes up and a couple down to each armpit. It’s as easy as that.

The timing of your deodorant application might be even more important than the method. Instead of applying it first thing in the morning, consider adding it to your personal hygiene routine the night before. “It’s most effective to use an antiperspirant at night,” says Dr. Garshick. “Antiperspirant is designed to plug up the sweat glands, which is easiest to do at night when the sweat glands aren’t active or filled with sweat. The sweat ducts are able to absorb more of the aluminum and therefore be more effective.”

Frequently asked questions about deodorant

What can I do if no deodorant works for me?

Having antiperspirant troubles? Unfortunately, sometimes deodorant’s effectiveness has nothing to do with the actual deodorant and more to do with how it’s interacting with the bacteria that lives on your skin. If your deodorant choices aren’t working out and are leaving you with body odor concerns, you may need to try out alternative methods. First give your armpits a chance to breathe for a few days—they may just need a reset. Then if you’re still experiencing deodorant failure, try a different type of deodorant than what your body is used to (natural vs. aluminum, for example) or opt for one of the alternatives above, such as using an antibacterial wash in the shower.

Why do I smell bad even with good hygiene?

You can still experience body odor even when your personal hygiene is top-notch. According to Dr. Garshick, the reason why all comes down to skin science. “Body odor refers to the odor that results from the combination of sweat and normal bacteria that live on the skin, with bromhidrosis being the medical term for foul-smelling body odor,” she says. “More specifically, the apocrine sweat glands—which are located in the underarm and groin area—produce sweat that is generally odorless. But it’s when the normal bacteria that live on our skin break down the sweat that odor may result—and what’s generally responsible for what most people consider body odor. This is why someone may notice a smell even with good hygiene.”

Which deodorant is best for odor?

If you’re experiencing antiperspirant troubles and are looking for dermatologist insights on the best deodorant for odor, Dr. Garshick has a couple options she swears by. “For those with excessive sweating looking for an effective antiperspirant that uses the same ingredient found in prescription strength antiperspirants, I recommend Certain Dri Prescription Strength Clinical Antiperspirant ($5),” she says.

For anyone who often has deodorant issues like irritation due to having sensitive skin, she recommends trying Certain Dri Extra Strength Clinical Antiperspirant Solid Deodorant ($9), “as it contains aluminum sesquichlorohydrate, which can provide up to 72 hours of protection.” Not a fan of aluminum? No problem: “For a pure deodorant to provide odor protection that’s aluminum-free, I recommend Dove 0% Aluminum, Cucumber, and Green Tea Deodorant Spray ($3), which will leave you feeling and smelling refreshed,” she says.

What is the most effective deodorant?

If you’re looking for an effective deodorant, Dr. Campbell says you’ll want to go with an antiperspirant, as it contains ingredients (like aluminum) that are able to control both sweat and body odor. Beyond that, does the type you choose matter? “Some people prefer a spray, as it’s easy to use and absorbs quickly without leaving a residue behind, while others don’t like to breathe in the aerosol spray,” says Dr. Garshick. “On the other hand, a stick, roll-on, or gel deodorant often helps to deliver controlled and precise coverage, but can potentially leave [underarm] residue or stains on shirts.”

Then there’s deciding between “wet” vs. “dry” options: “Roll-ons (which are liquid-based) and gel-based deodorants often go on wet and then dry after a few seconds, while stick deodorants typically go on dry and don’t require significant drying time, which can be helpful for someone on the go,” she says. All in all, she notes that it all comes down to personal preference and whatever works best for you.