Quick answer. Most excessive sweating is primary hyperhidrosis – sweating limited to areas like the hands, feet, armpits or face that is harmless but troublesome. New, generalised sweating (especially at night) with weight loss, fever or a racing heart can signal an underlying problem and should be checked by a doctor.
Sweating is how your body cools itself, but some people sweat far more than they need to. When sweating is focused on the hands, feet, underarms or face, it is usually primary (focal) hyperhidrosis – common, benign and often starting in childhood or the teens.
Sweating that is new, all over the body, or happens at night can be secondary to another condition such as an overactive thyroid, diabetes, infection or hormonal change. This guide explains the difference and the warning signs that mean you should see a doctor.
At a glance
| Pattern / cause | What it may suggest | Urgency |
|---|---|---|
| Localised to hands, feet, armpits or face since youth | Primary (focal) hyperhidrosis – usually benign | Routine – see a doctor if it affects daily life |
| Heat intolerance, racing heart, weight loss, tremor | Overactive thyroid (hyperthyroidism) | See a doctor soon |
| Sweating with excessive thirst, frequent urination, tiredness | Possible diabetes or blood sugar swings | See a doctor soon |
| Hot flushes and sweats around the menopause | Hormonal (perimenopause/menopause) | Routine – see a doctor if bothersome |
| New generalised or night sweats with fever or weight loss | Possible infection or other underlying illness | See a doctor promptly |
Red flags: when sweating needs urgent attention
See a doctor promptly if your sweating is new and comes with any of these:
- Drenching night sweats that soak your bedding
- Unexplained weight loss, persistent fever or swollen glands
- A racing or irregular heartbeat, tremor or marked heat intolerance
- Sweating that suddenly becomes generalised (all over) rather than focal
- Chest pain, light-headedness, nausea or cold clammy skin – if these come on suddenly, call 995 as this can signal a heart problem.
These features point to a possible underlying cause that needs investigation rather than simple focal hyperhidrosis.
What counts as "excessive" sweating?
Excessive sweating, or hyperhidrosis, means sweating more than the body needs for temperature control. People with focal hyperhidrosis may sweat through clothing, struggle to grip pens or phones, or avoid handshakes and social situations. The amount is more than would be expected for the temperature or activity level, and it can happen even when you are cool or resting.
Common and benign causes
Primary focal hyperhidrosis is the most common cause. It affects specific sites – typically both palms, both soles, the underarms or the face – usually starts before adulthood, often runs in families, and tends to ease during sleep. It is not dangerous, though it can affect confidence and daily tasks. Hot, humid weather (very relevant in Singapore), spicy food, caffeine, exercise and anxiety can all make normal sweating heavier without any disease being present.
Underlying (secondary) causes to consider
When sweating is new, generalised or happens at night, doctors look for a secondary cause. These include an overactive thyroid, diabetes or low blood sugar, infection, hormonal changes such as menopause, certain medications, and less commonly some blood cancers (such as lymphoma). Because several of these are hormone-related, an endocrinologist is often involved, alongside blood tests arranged by your GP or specialist.
Which specialist should you see?
Start with your GP, who can take a history, examine you and arrange blood tests (for example thyroid and blood sugar). If a hormonal or metabolic cause is suspected, you may be referred to one of the endocrinologists. If the problem is purely focal sweating of the skin and you want treatment options such as antiperspirants, iontophoresis or injections, the dermatologists are the right specialists.
How excessive sweating is assessed and managed
Assessment usually starts with questions about where, when and how long you have been sweating, plus a check for other symptoms. Blood tests may be done to rule out thyroid problems, diabetes or infection. For focal hyperhidrosis, treatments range from strong antiperspirants and iontophoresis to prescription medicines, injections that block sweat signals, and in selected cases surgery. Where a secondary cause is found, treating that condition usually settles the sweating.
How to prepare for your appointment
A little preparation helps your doctor reach the right answer faster. Before you go, note where you sweat (hands, feet, underarms, face, or all over), when it started, and whether it happens at rest, at night, or only with heat and activity. Mention if it runs in your family and whether it eases during sleep, as these point towards primary focal hyperhidrosis. Equally important are the symptoms that suggest a secondary cause: weight loss, a racing heart, tremor, fever, excessive thirst or frequent urination. Bring a list of your current medicines and supplements, since some can increase sweating.
What to expect at the appointment
Your GP will take a history and examine you, then decide whether blood tests are needed. These may include thyroid function and blood glucose to check for an overactive thyroid or diabetes, and sometimes a full blood count if infection or another illness is suspected. If your sweating is clearly focal and long-standing, the focus shifts to managing the sweating itself rather than searching for an internal cause. You will not usually need scans for simple focal hyperhidrosis. The doctor may grade how much the sweating affects daily life, which helps guide treatment choices and any referral.
Self-management at home
While you wait to be seen, a few measures can reduce day-to-day sweating. Wear loose, breathable cotton or moisture-wicking fabrics, change socks during the day, and keep feet dry to lower the risk of fungal infection in Singapore’s humidity. Strong aluminium-chloride antiperspirants, applied to clean, dry skin at night, are a sensible first step for underarms and can also be used on palms and soles. Cutting back on caffeine, alcohol and very spicy food may help if these are clear triggers. Managing stress through regular sleep, exercise and relaxation can soften anxiety-driven sweating, though it will not resolve a true secondary cause.
Costs and subsidies in Singapore
A GP consultation and basic blood tests are the usual starting point. Singapore Citizens may be able to use Community Health Assist Scheme (CHAS) subsidies at participating private GP clinics, and polyclinics also offer subsidised consultations and tests; eligibility and amounts depend on your card tier and the clinic. Specialist treatments for focal hyperhidrosis, such as iontophoresis or injections, are generally paid out of pocket and vary widely, so ask the clinic for a written estimate beforehand and check what any insurance covers.
Common questions
Is sweating a lot always a sign of something serious?
No. Most excessive sweating is harmless focal hyperhidrosis. It is the new, generalised or night-time sweating, especially with weight loss, fever or a racing heart, that needs checking for an underlying cause.
Can I treat focal hyperhidrosis without surgery?
Yes. Most people manage well with strong antiperspirants, iontophoresis, prescription medicines or injections. Surgery is reserved for selected, severe cases that do not respond to other treatments.
Does drinking less water reduce sweating?
No, and it can be harmful in a hot climate. Stay well hydrated; sweating reflects your sweat glands’ activity, not how much you drink.
Related guides
- Best Endocrinology & Diabetes Clinics in Singapore — our editorial shortlist
- endocrinology & diabetes clinics directory
- Excessive thirst
- Itchy skin all over
- Easy bruising & bleeding
Sources
- NHS – Excessive sweating (hyperhidrosis)
- Mayo Clinic – Hyperhidrosis
- NHS – Overactive thyroid (hyperthyroidism)
- SingHealth – Conditions & Treatments
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