am i dying

Am I Allergic to My Own Sweat?

Photo: De Agostini Picture Library/De Agostini/Getty Images

Welcome to Am I Dying, a column that hopes to save you from your late-night WebMD spiraling. You can email us your hypochondriac questions at amidying@nymag.com.

Am I allergic to sweat? Whenever I work out aggressively and I get all sweaty, I feel itchy. Or is this just what being sweaty feels like, and I never get sweaty, so I never know…? I don’t know, I feel SO itchy when I’m sweaty. I’ve diagnosed myself with a sweat allergy without googling whether it is possible. Is that real? Help.

I, too, sometimes feel itchy after working out, and up until now, I assumed it had something to do with sweat being salty and therefore drying your skin out. But when I asked a dermatologist — specifically, Arielle Nagler, an assistant professor of dermatology at NYU Langone Health — and she told me that while my theory was clever and logically sound (my words, not hers), it’s also inaccurate. “Sweat theoretically could be considered drying, because it evaporates, and can leave you more dry, but I don’t think that’s usually [the cause of itchiness],” she tells me.

Neither is the cause of your itchiness a sweat allergy, says Nagler — but it’s possible the culprit is a reaction initiated by your sweat. “People aren’t really allergic to sweat because it’s made by their own body,” she explains. “Things that cause allergies are foreign things that your body attacks. So instead of sweat, it could be that sweat changes something about someone’s deodorant or a fragrance, and that could be triggering the allergy.” If you go to the gym with perfume on, for instance, it’s possible for sweat to enhance an underlying irritation you might already have to that product, but which usually goes unnoticed.

Another factor to consider: are you, unlike me, who would definitely never laze around the apartment in yoga pants and a sports bra for hours after going to the gym, wearing your exercise clothes for significant periods of time post-workout? If so, that might be your problem. “If you exercise and stay in your workout clothes for hours, you can get these little yeast overgrowths which can be itchy,” says Nagler. “Warm environments promote yeast. And wicking products especially tend to be really occlusive and itchy, so changing immediately and trying to shower can be really helpful.” Your sweat-wicking tank top might help keep you drier while exercising, but it also blocks airflow, and keeps that part of your body warmer, which makes it all the more likely to get itchy.

Even if you aren’t wearing scented, possibly allergy-inducing products to the gym, or keeping your leggings on for hours afterward, it’s also possible your skin is just sensitive to exercise itself, says Nagler. “Sometimes people can actually get hives when they’re exercising,” she says. “One sign you have of this is if you start scratching you end up getting red lines or welts in the areas that you’ve scratched.” What exactly causes this reaction varies, and isn’t always obvious, says Nagler — it could, for instance, be a viral trigger that comes and goes. Many people who experience this sort of reaction will only experience it for a certain period of time and then never again, she adds. But generally speaking, sweating a lot (even if it’s a little itchy) isn’t something you should worry about.

“Sweating isn’t dangerous,” says Nagler. “If you’re having itchy reactions associated with other symptoms, like throat swelling, or tongue swelling, or shortness of breath beyond the normal shortness of breath associated with exercise, those things can be concerning, but there’s no concern with too much sweating.” Sweat is your body’s way of cooling you off, and that’s a good thing. But if your sweating and subsequent itchiness are having a negative impact on your life, there are things you can do, says Nagler — among them, Botoxing your armpits, taking over-the-counter allergy medications (ones without a decongestant — that won’t help), and using aluminum chloride based deodorants like Certain Dri can all help in certain cases. But if this continues to bother you, Nagler recommends you see a dermatologist, who can help you decide between these options and others.

Am I Allergic to My Own Sweat?