Why Do I Sweat So Much? Hyperhidrosis May Be the Cause

Take it from this Italian girl: The fear of sweating too much at the wrong moment or while wearing the wrong outfit (hello, silk), is a very real thing. Many times, I have asked myself, "Do I sweat too much?" But where do you draw the line between normal and excessive sweating, exactly? As it turns out, hyperhidrosis, the medical term for excessive sweating, is more common than you might think, especially if you're one of the (many, many) people who are afraid that they sweat more than other people around them. What's more, hyperhidrosis is surprisingly easy to treat.

We consulted dermatologists, cosmetic chemists, and surgeons to learn exactly which symptoms to look out for, which treatment options may help stop sweating, and how to tell if your perspiration predisposition is typical or over-the-top. Plus, are aluminum chloride antiperspirants safe to use every single day? And, is it OK (i.e. not unhealthy) to get sweat-halting Botox injections before a special day like a wedding, family celebration, or some other major life event?

• Lily Talakoub, MD, is a board-certified dermatologist based in McLean, Virginia.
• Dhaval Bhanusali, MD, is a board-certified dermatologist based in New York City.
• Lyall Gorenstein, MD, is a board-certified thoracic surgeon and the surgical director at Columbia University Hyperhidrosis Center.
• Ron Robinson is a cosmetic chemist and founder of Beautystat.
• Estee Williams, MD, is a board-certified dermatologist and assistant clinical professor in dermatology at Mount Sinai Medical Center in New York City.

• What is hyperhidrosis, exactly?
• What's the difference between normal vs. excessive sweating?
• How is hyperhidrosis treated?
• If you use Botox injections to stop sweating, will you overheat?

Hyperhidrosis is "the excessive production of sweat" by the body, explains Lily Talakoub, MD, a board-certified dermatologist at McLean Dermatology in Virginia.

There are two types of hyperhidrosis: primary and secondary.

The most common type is primary hyperhidrosis, which has no known underlying physical cause. "Primary hyperhidrosis is due to overactive signaling of sweat glands to secrete sweat without stimuli," explains New York City-based dermatologist Dhaval Bhanusali, MD.

In other words, your body starts sweating without any explicable reason (like feelings of anxiety, hot temperatures, or exercise). This kind of hyperhidrosis can occur at any given time or during any season of the year, even if the person is not physically warm or is completely at rest. "Primary hyperhidrosis is most commonly seen in the underarms, palms, and soles of the feet," says Dr. Bhanusali.

Other less-common areas where primary hyperhidrosis's excessive sweating can pop up include the head, back, and even the face. So basically, it can pretty much happen anywhere on your body.

Secondary hyperhidrosis, on the other hand, is excessive sweating that's caused by an external factor such as medication or illness, like a tumor, diabetes, or thyroid issues.

Of these two types, there are also different degrees of hyperhidrosis that experts differentiate between: mild, moderate, and severe. "If you sweat through a shirt when you are at rest in normal temperature, I would say that is moderate hyperhidrosis," Dr. Talakoub says. "If you have sweat dripping down your hands and through your socks [when you're] at rest with no [other] triggers, then that is severe hyperhidrosis."

Of course, the next question then becomes: What's the threshold between normal and worrisome sweat levels? Are there any other symptoms to look out for that don't involve perspiration?

"Excessive sweating, or how someone perceives it, is very personal in that what might be excessive to you is normal or not troubling to somebody else," explains Lyall Gorenstein, MD, surgical director at Columbia University Hyperhidrosis Center.

Because sweat is not really a quantifiable thing, like blood pressure, it's really complicated to measure someone's sweat levels throughout any given day. With enough time and "sophisticated equipment" called an evaporimeter — which measures the rate of water evaporation — it is doable, but even so, "there's a big variability in how much people sweat under similar situations," Dr. Gorenstein says. "So, it's hard to define exactly what hyperhidrosis is, but it could be something along the lines of increased amounts of sweating, which causes social or personal embarrassment, withdrawal, and/or avoidance behavior."

That is to say, hyperhidrosis is a relative disorder and most people diagnose it themselves. For someone whose job depends on their physical appearance, like an actor or a performer, sweating too much may be a bigger deal than for someone who works from home. But it's also a matter of personal comfort levels. 

Good news: There are many hyperhidrosis treatment options, including topical creams, injections, and oral medications. What your physician prescribes will likely depend on the area where you're experiencing hyperhidrosis as well as the severity.

The first line of treatment is usually topical aluminum chloride, aluminum chlorohydrate, aluminum zirconium, or aluminum zirconium tetrachlorohydrex gly, which are the same ingredients found in most antiperspirant deodorants, just in prescription-strength form. "All aluminum ingredients in antiperspirant products work to control wetness by forming a temporary plug within the sweat gland," cosmetic chemist Ron Robinson has previously told Allure. The effectiveness of this treatment varies, depending largely on the severity of the sweating — generally, the more severe it is, the less likely that aluminum chloride products will be effective. They will, however, work for mild hyperhidrosis, although the creams have to be applied to the affected areas every day.

Another longer-lasting treatment, which you've probably seen advertised on TV and in magazines, is Botox therapy. Yes, the very same injectable that you might get to prevent wrinkles between your brows can also help stop excessive sweating. "In under three minutes, they go from being super-sweaty to nearly dry," board-certified dermatologist Estee Williams, MD, has told Allure of treating hyperhidrosis patients with Botox. "The dose can be tailored to the degree of dryness that they want." 

Experts agree that Botox is most effective in the underarm area, where it can work for up to six months. On other areas of the body, however, such as the hands and feet, Botox isn't the best line of treatment because it's both painful and only lasts two to three months, Dr. Gorenstein explains.

Another option that's relatively new is Qbrexza, which is a medicated cloth towelette that temporarily stops sweating when worn in your underarms; it's anticholinergic, which means it blocks neurotransmitters associated with sweat glands. Other possible options include laser treatments (also most effective in the underarm area) and even oral drugs such as beta-blockers and antidepressants, although the results are mixed and, of course, they can also present other unwanted side effects.

For really, really severe cases of hyperhidrosis, there's an endoscopic thoracic sympathectomy: an outpatient surgical procedure where signals in the sympathetic nerve in the chest are permanently interrupted.

For the rest of us who are perhaps prone to what feels like over-sweating yet not to the point of seeking medical help, there are always trusty over-the-counter antiperspirants that have a higher percentage of the active ingredient, like Secret Clinical Strength Soft Solid and Degree Clinical Protection — both have 20 percent aluminum zirconium tetrachlorohydrex gly. 

This was my biggest question because sweating happens naturally for a physiological reason, right? So, is stopping your body from its natural sweating process unhealthy in the long term?

"No, not really," Dr. Gorenstein says. "The function of sweating is to eliminate waste products [from the body], but minimally compared to the liver and kidneys," he says. "Sweating [also] allows you to cool yourself as the body heats, but you have sweat glands all over your body so even if you're not sweating in your underarms, you're not ever going to overheat."

So, no, it's not "unhealthy" to get a few shots of Botox in your underarms before a big event or even to continue the treatment indefinitely. However, if you do think you have hyperhidrosis, it's very important to consult a board-certified dermatologist who can rule out any underlying medical causes.

More on antiperspirant and deodorant:

• The 11 Best Antiperspirant Deodorants of All Time
• Degree Designed a Deodorant for People With Disabilities
• Dr. Sweat Antiperspirant Pads Keep My Underarms So Dry

Now see how deodorant has evolved within the last 100 years: