Everybody sweats, and sweating is how the body keeps from overheating. Hyperhidrosis is sweating well beyond what the body needs: soaking through shirts in a cool room, leaving damp handprints on paper, changing clothes midday, or planning outfits around what will hide the marks. It is not dangerous in itself, but it can affect work, relationships and confidence, and it is very treatable.
At NYMD Center we approach excessive sweating the way internal medicine physicians approach any symptom: first we make sure nothing else is causing it, then we treat it, starting with the simplest measures. Many people are relieved to learn that heavy sweating is a recognized medical condition and not a hygiene problem.
We care for adults only; children and teenagers with excessive sweating should see a pediatrician.
Primary and secondary hyperhidrosis
There are two broad kinds. Primary focal hyperhidrosis is the most common. According to Cleveland Clinic, it usually affects the underarms, hands, feet or face, typically begins before age 25, and often runs in families. It happens while you are awake, tends to affect both sides of the body evenly, and has no underlying disease behind it. The nerves that signal the sweat glands are simply overactive.
Secondary hyperhidrosis is caused by something else. MedlinePlus lists thyroid problems, diabetes, menopause, infections, heart disease, anxiety and certain medications among the causes. Secondary sweating is more likely to be generalized over the whole body, to start later in life, to begin suddenly, or to happen during sleep. Night sweats, especially with fever, weight loss or fatigue, always deserve a medical evaluation.
How we evaluate excessive sweating
The visit begins with questions: where you sweat, when it started, whether it happens at night, whether anyone in your family has the same problem, and what you have already tried. We review every medication and supplement, since some antidepressants, pain relievers, diabetes medicines and thyroid hormone can increase sweating. For women in midlife we ask about periods, hot flashes and sleep, because menopause is a common and treatable cause.
A physical examination follows, and when the pattern suggests a secondary cause we order blood work, usually including thyroid function, blood sugar and a blood count, with other tests added as needed. An overactive thyroid is a classic cause and is covered on our thyroid disease page. If blood sugar problems turn up, that becomes the focus. When an underlying cause is found, treating it often reduces the sweating on its own.
Treatment options
Clinical-strength and prescription antiperspirants
The first step is an antiperspirant containing aluminum chloride, which plugs the sweat ducts. Over-the-counter clinical-strength products help some people; prescription-strength versions help more. Mayo Clinic advises applying it to dry skin at bedtime, washing it off in the morning, and cutting back to once or twice a week once it is working. Skin irritation is the main drawback, and it can often be managed by adjusting how often you use it.
Botox injections for underarm sweating
When antiperspirants are not enough, Botox injections are the next step for the underarms. Botulinum toxin blocks the nerve signal that switches on the sweat glands in the treated skin. The American Academy of Dermatology notes that it is FDA approved to treat hyperhidrosis, that most patients notice less sweating within 7 to 10 days, and that results in the underarms last roughly 3 to 10 months. Treatment involves a series of small, shallow injections across each underarm and takes a short office visit. The trade-offs are that it wears off and must be repeated, and that there can be brief soreness or bruising at the injection sites. It is a medical use of Botox, separate from its cosmetic use, and insurance coverage varies.
Prescription oral medication
Some people need more. Our physicians can prescribe oral medications that reduce the nerve signals to sweat glands. They can help widespread sweating but may cause dry mouth, blurred vision or constipation, so we start at a low dose and review how you do.
Options available by referral
Iontophoresis, which uses a mild electrical current through water, works best for the hands and feet and needs repeated sessions. Device treatments that destroy underarm sweat glands, and surgery on sweat glands or on the nerves that control them, are reserved for severe cases and carry real risks, including compensatory sweating elsewhere after nerve surgery. We can discuss whether these make sense for you and refer you to a dermatologist or surgeon who provides them.
Everyday measures
Breathable fabrics, moisture-wicking socks, changing socks during the day, absorbent pads for clothing and limiting triggers such as alcohol and very spicy food all help alongside medical treatment.
What to expect at your visit
Your first visit is a medical evaluation with a physician, not a sales conversation. Expect a detailed history, a medication review, an examination and, when it is warranted, blood tests. If the sweating looks primary and focal, we will start or adjust antiperspirant treatment and discuss whether Botox is a good next step. Underarm Botox is performed through our medical spa team and can be scheduled once you and your provider agree on it.
When to seek care urgently
Sweating that comes with chest pain or pressure, shortness of breath, nausea or lightheadedness can be a sign of a heart attack; call 911. In people with diabetes, sudden sweating with shakiness, confusion or a racing heart can mean low blood sugar and needs immediate treatment. See a physician promptly for drenching night sweats, sweating with fever or unexplained weight loss, or new heavy sweating on only one side of the body.
Questions patients ask
Is excessive sweating a medical condition?
Yes. Hyperhidrosis is a recognized medical condition in which the sweat glands produce more sweat than the body needs to stay cool. The primary form often runs in families and affects the underarms, hands, feet or face. The secondary form is caused by something else, such as thyroid disease, diabetes, menopause, infection or a medication, which is why an evaluation comes before treatment.
Does Botox really stop underarm sweating?
It greatly reduces it for most people. Botox blocks the nerve signal that activates sweat glands in the treated skin. The American Academy of Dermatology notes that most patients notice less sweating within 7 to 10 days and that underarm results last roughly 3 to 10 months. The effect is temporary, so treatment is repeated when sweating returns.
What should I try before Botox?
Start with an antiperspirant containing aluminum chloride, first over-the-counter clinical strength and then a prescription version if needed. It works best applied to completely dry skin at bedtime and washed off in the morning. Breathable clothing and absorbent pads help too. If these do not give enough relief, or cause too much skin irritation, Botox is the usual next step for the underarms.
Can excessive sweating be a sign of something serious?
Sometimes. Sweating that starts suddenly in adulthood, covers the whole body, happens mainly at night or comes with fever, weight loss or fatigue can point to an underlying problem such as an overactive thyroid, diabetes, infection or, less often, other illness. Sweating with chest pain or shortness of breath needs emergency care. That is why we check for medical causes first.
Is Botox for sweating covered by insurance?
It depends on your plan. Because treating hyperhidrosis is a medical use rather than a cosmetic one, some insurers cover it, often only after you have tried prescription antiperspirants and with documentation from your physician. Other plans do not cover it. Our staff can tell you what information your insurer needs when you call to schedule.