13 signs your excessive sweating is a sign of a serious medical condition
For most people, sweating is a normal and natural way for the body to help regulate its temperature and cool itself down when temps rise. But for some people, sweating is an abnormally constant part of life, soaking shirts and dampening hands no matter the weather or level of activity.
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Sweating is the body's natural response to hot temperatures, physical activity, and even stress. But some people have hyperhidrosis, which causes them to sweat excessively in other situations too.
For many people with hyperhidrosis, the condition is manageable and not concerning. For others, it's a sign of a more serious medical issue, like a heart attack, infection, thyroid problem, or even cancer.
If you sweat excessively and aren't sure why, visit your doctor to rule out underlying medical issues and develop a treatment plan.
For most people, sweating is a normal and natural way for the body to help regulate its temperature and cool itself down when temps rise. But for some people, sweating is an abnormally constant part of life, soaking shirts and dampening hands no matter the weather or level of activity.
In these cases, excessive sweating is known as hyperhidrosis, which WebMD reports affects 2% to 3% of Americans. For the most part, hyperhidrosis isn't something to be too concerned about. If you're not experiencing any secondary side effects (like heat rash or skin infections) and are able to go about your normal activities, it can be little more than a nuisance that requires extra breathable clothing and strong antiperspirants.
But excessive sweating can also indicate an underlying health concern. And sometimes, it can be tricky to know the difference. INSIDER spoke with two physicians about how to know if your sweating is a sign of a bigger problem.
Excessive sweating comes on suddenly and unexpectedly
Sudden, unexpected sweating could be a sign you're stressed or anxious. This type of sweat is different from the perspiration that results from your body's attempts to cool you down because it's caused by a "surge in adrenaline," or your body's fight-or-flight response, explained Dr. Caesar Djavaherian, cofounder and chief medical officer at Carbon Health who's based in Berkeley, California
Unexpected sweating could also be "the first sign of a heart attack or an underlying heart problem," he added. If you suspect you're experiencing a heart attack, you'll want to reach out for emergency help as quickly as possible.
That said, a sudden onset of sweating isn't always a reason to panic. It "can come with certain situations, such as with warmer temperatures, spicy foods, exercise, or stress, and doesn't always mean there's a more significant underlying condition," said Dr. Marisa Garshick, a dermatologist in New York City and chief medical correspondent for Certain Dri, an over-the-counter antiperspirant. You should address any concerns with your doctor.
You also feel faint, dizzy, or lightheaded
When sweating is accompanied by a feeling of dizziness or lightheadedness, it may signal an underlying health issue like low blood sugar levels, or hypoglycemia, which may be caused by a drop in blood pressure, according to Djavaherian.
While these symptoms on their own might not seem troubling, check in with your doctor to ensure there's no underlying cause for concern.
The sweating is accompanied by insomnia, flushing, chest pain, seizures, fatigue, or increased thirst and urination
Taking stock of your overall health can help determine if excessive sweating is part of a larger issue. Insomnia plus sweating, for example, can be a sign of hyperthyroidism, Garshick said.
Sweating along with flushing (when your face and chest feel hot and change color) may signal carcinoid syndrome, or when a rare cancerous tumor secretes certain chemicals into your bloodstream, according to the Mayo Clinic.
Excessive sweating paired with chest pain sometimes indicates a serious heart condition, so "it's important to always to seek immediate medical attention if you are experiencing chest pain," Garshick said.
Seizures accompanied by sweating, meanwhile, usually means people are experiencing a medication overdose, Djavaherian said. Sweating with fatigue could mean an infection or low blood pressure.
Finally, increased thirst and urination is associated with diabetes and blood glucose levels. "Sometimes, people will sweat if their blood glucose drops, such as an early warning sign of stress or strain," Djavaherian said.
You're also experiencing flu-like symptoms, including a fever or cough
Sweating accompanied by a fever may reflect a bacterial or viral infection like malaria or tuberculosis, which is also accompanied by a cough, Garshick said.
"A fever is the result of a change in body temperature — your brain automatically sets your body temperature a little higher to fight the infection present in your body, which leads to feeling cold and generating heat," Djavaherian said. "This is why it is necessary to break a fever by regulating the body temperature and sweating it out."
Often, as the fever breaks, Garshick said, people experience an increased amount of sweat.
You're experiencing other skin issues such as rash or hives
If sweat stays on your skin, you might experience itching or irritation that will go away on its own once you stop sweating or change into clean, dry clothes. But experts say that skin issues like a rash or hives might be indicative of a fungal skin infection or another medical condition.
"There are some skin conditions that can occur in association with sweating, such as cholinergic urticaria, which can cause hives in some people when the body gets hot and sweaty," Garshick said. "There are also skin rashes that can occur as a result of excessive sweating in hot or moist environments, such as heat rash or prickly heat, also known as miliaria."
As always, check in with your doctor or dermatologist to help pinpoint the cause of your skin concerns.
Excess sweating can be a side effect of some medications, or a sign that the dosage should be adjusted. PexelsYou started a new medication or a change in dosing
Sweating is a surprisingly common side effect of several medications, including:
Stimulants like amphetamines and caffeine
Some diabetic medications like sulfonylureas
Pain medications including opioids
Various psychiatric medications
Hormonal medications like birth control pills
Thyroid medications
Oral steroids
Since sweating is an expected side effect of some medications and can signal that the dose may need to be adjusted in others, it's something to discuss with a doctor, Garshick said.
You're under a lot of stress or experiencing panic attacks
Lots of people sweat in stressful situations, like before public speaking. But if sweating is accompanied by other symptoms of panic or anxiety, you'll want to check in with a doctor or therapist, who can help correctly diagnose any underlying mental health concerns.
"Intense emotion and stress can bring out sweating in anyone," Garshick said. "If you experience panic attacks or increased levels of stress related to a persistent and excessive worry about everyday situations, this can mean that you are also experiencing anxiety."
Anxiety-related sweating can be a vicious, self-perpetuating cycle in which the anticipation of sweating actually causes you to sweat. The good news is there are plenty of medication-based and therapeutic treatments to help ease these worries. Seeing a professional may help both manage the anxiety and the sweat.
You're withdrawn socially or you feel anxious in everyday situations
If you find that you're fearful of or avoiding certain situations due to the possibility of sweating, discuss it with a trusted doctor or therapist, who can help you manage these feelings and symptoms.
"It is known that excessive sweating can have an impact on quality of life, impacting people's relationships, work, and daily life, and this can occur no matter what the reason behind the sweating is," Garshick said. A 2019 study even showed that people who experience primary hyperhidrosis, or excessive sweating without a cause, have higher rates of anxiety, depression, and attention deficit disorder than the general population.
You're also experiencing sudden weight loss
If you're rapidly losing weight and sweating excessively, you may have a thyroid condition like hyperthyroidism. Infections including tuberculosis and mononucleosis, as well as certain types of cancers, can lead to these symptoms too, Garshick said.
"If you're experiencing sudden weight loss and sweating, it can mean many different things and is important to see a board-certified physician," she said.
You're sweating all over your body instead of in just one area, like the armpits or face
All-over body sweating can occur in various forms of secondary hyperhidrosis, or sweating that is caused by or associated with another disorder or medication. (Primary hyperhidrosis, meanwhile, tends to refer to excessive sweating that is in specific places like the armpits, face, or palms.)
Still, most of the time, generalized sweating is a normal reaction to heat, stress, or exercise, Djavaherian said. If you're unsure whether your experience is normal, checking with your doctor is the best course of action.
Most people experience night sweats when it's hot outside or the temperature in their bedroom is too high. But if you're keeping the temperature in your room cool, using breathable fabrics and bedding, and still sweating excessively at night, you might have a medical concern at hand.
"Night sweats can mean an infection such as tuberculosis or the flu, or it can [be a sign of] certain types of cancer such as lymphoma," Garshick said. "It can also be related to hormonal changes such as menopause or due to a medication." Substance abuse and withdrawal can also lead to night sweats, she added.
Sweating only occurs on one side of the body
If you notice sweating only on one side of your body, you might want to check in with your doctor. Uneven sweating "can indicate a rare nervous system disorder called Harlequin syndrome, Garshick said. It could also indicate a brain tumor, abscess, or stroke, she added.
Lung cancer and Horner's syndrome, an issue with a nerve pathway, can also be tied to sweating on one side of the body, Djavaherian said.
Though sometimes embarrassing, for most people, sweating is a normal part of being human. DWaschnig/Shutterstock
You sweat for no apparent reason
If you and your doctor have ruled out all potential underlying medical conditions and other causes (like eating spicy foods or working out), you might simply have overactive sweat glands.
"Some people have overactive sweat glands, so even the smallest stimulation will cause them to sweat," said Djavaherian, adding that this isn't necessarily "a sign of a bigger problem."
It also can be quite manageable with treatments like antiperspirants. "If that's not enough," Garshick said, "you can speak with a board-certified dermatologist regarding other treatment options including prescription antiperspirants, oral medications, topical wipes, Botox injections, and more."
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