Medically reviewed guide · Last updated: 23 July 2026 · Reading time: approx. 9 min.

Excessive sweating:
harmless or a warning sign?

At a glance

What is it?Sweating well beyond what the body needs for cooling — medically known as hyperhidrosis
Usually harmless?Often yes — especially the primary form on the hands, feet or armpits with no underlying condition
Common triggersPredisposition, stress, heat, menopause, an overactive thyroid, certain medications
Warning signsNew, heavy night sweats with fever, weight loss and fatigue — then get it checked quickly
Key distinctionLocal & without a cause (primary) versus all over the body with an underlying condition (secondary)
What to doStep-by-step treatment: antiperspirant with aluminium chloride, then iontophoresis, Botox, medication

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Table of contents

  1. What is excessive sweating?
  2. Primary or secondary — harmless or dangerous?
  3. Causes & triggers
  4. Self-check: what to look out for
  5. When to see a doctor?
  6. Diagnosis
  7. What you can do yourself
  8. How brite helps you
  9. FAQ
  10. Related topics

1. What is excessive sweating?

Sweating is vital: through sweat the body regulates its temperature and protects itself from overheating. With excessive sweating (hyperhidrosis), however, the sweat glands produce far more fluid than is needed for cooling — often even when it is neither warm nor there is any physical exertion. Those affected have, for example, wet hands, sweat-soaked armpits or damp feet even though there is no outward reason for it.

Excessive sweating is common and a real burden in everyday life for many people — when shaking hands, at work or in social situations. The good news: in many cases there is no dangerous condition behind it, and there is a whole range of effective treatments. The key is to recognise the right form.

The most important point first Two forms are distinguished: primary hyperhidrosis (usually confined to a local area on the hands, feet or armpits, with no recognisable cause) and secondary hyperhidrosis (all over the body, triggered by a condition or a medication). This distinction determines how it is investigated and treated.

2. Primary or secondary — harmless or dangerous?

The most important question is not "am I sweating too much?", but "where do I sweat and since when?". That is exactly how the two forms can be told apart:

FeaturePrimary hyperhidrosisSecondary hyperhidrosis
LocationLocal: hands, feet, armpits, headAll over the body (generalised)
CauseNo underlying condition, often a predispositionA condition or a medication
OnsetUsually already in adolescence/young yearsOften new, in adulthood
During sleepUsually not (pause at night)Often also at night (night sweats)
Table scrolls to the right

The primary form is unpleasant but harmless to health. It often begins in adolescence, occurs at clearly defined spots and usually takes a break at night. The secondary form is therefore more important to classify: if the sweating is new, affects the whole body or occurs at night, a treatable cause may be behind it — from an overactive thyroid through the menopause to a medication.

3. Causes & triggers

With primary hyperhidrosis there is usually no pathological cause — the sweat glands simply react over-sensitively, often running in the family. With the secondary form, on the other hand, it is worth looking at possible triggers:

  • Hormonal changes: above all the menopause with hot flushes, but also pregnancy or an overactive thyroid.
  • Stress and tension: excitement, nervousness and inner restlessness particularly drive sweating on the hands and armpits.
  • Fever and infections: the body heats up and sweats to cool down — temporary and usually harmless.
  • Medications: a very common, often overlooked cause — more on this shortly.
  • High and low blood sugar: in diabetes, low blood sugar can trigger sweating episodes.
  • Excess weight and alcohol: both promote increased sweating.
  • Rarer causes: certain cancers (e.g. lymphomas) can be accompanied by night sweats — which is why new, marked night sweats are a warning sign (see the chapter "When to see a doctor").
Medications as a common cause Numerous active substances can trigger excessive sweating — often without the connection being noticed. These include certain antidepressants, especially SSRIs such as Sertraline, as well as opioids (strong painkillers), some thyroid and diabetes medications, and fever-reducing agents. Never stop a medication on your own — discuss any suspicion with your doctor.

The timing in relation to a new medication or a life phase such as the menopause is something you can observe well yourself. A simple log helps to spot patterns.

4. Self-check: what to look out for

Before you have excessive sweating investigated, it helps to observe your own pattern a little. These questions give the doctor important clues as to whether it is more likely the primary or the secondary form:

  • Where do you sweat? Only at certain spots (hands, feet, armpits) or all over the body?
  • Since when? Ever since adolescence, or newly appeared in adulthood?
  • At night too? Do you wake up soaked in sweat and perhaps have to change your bedclothes?
  • Accompanying symptoms? Do fever, unintended weight loss, a racing heart or fatigue come with it?
  • New medication? Did the sweating begin with a new preparation or a change in dose?

Locally confined sweating since adolescence that takes a break at night points to the harmless primary form. New, generalised sweating — especially with night sweats or accompanying symptoms — should be assessed by a doctor.

Your sweating log always to hand

With brite you record when and where you sweat, which triggers and medications play a role — the best basis for the doctor to quickly get to the bottom of the cause.

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5. When to see a doctor?

Excessive sweating is often harmless, but there are situations in which you should have it investigated or act immediately.

You should have it assessed by a doctor promptly if the sweating is new and all over the body, is a heavy burden in everyday life, began with a new medication, or if you wake up at night soaked in sweat. It is also worth seeing a doctor if the sweating restricts you a great deal at work or socially — there are effective treatments.

Take warning signs seriously — get them checked quickly Newly appeared, marked night sweats together with fever, unintended weight loss and severe fatigue (so-called B symptoms) must be investigated by a doctor promptly, as rarely serious conditions can be behind them. If sweating occurs suddenly with chest pain, tightness or shortness of breath, a heart problem may be present — then call the emergency number 112 immediately.

6. Diagnosis

To find the cause, the doctor has simple and informative examinations available. It is important to describe the sweating as precisely as possible.

ExaminationWhat it shows
Medical historyLocation, onset, night sweats, accompanying symptoms, medications
Physical examinationAffected areas, signs of underlying conditions
Blood testThyroid values, blood sugar, inflammation and blood values
Iodine-starch test (Minor test)Makes the sweat areas visible, delineates them
Further investigationTargeted additional diagnostics if serious causes are suspected
Table scrolls to the right

The most important step is the conversation: whether the sweating is local or generalised, when it began and whether it occurs at night often already points the way. A well-kept log and a complete list of medications make the classification considerably easier.

7. What you can do yourself

For excessive sweating there is a proven step-by-step therapy — from simple and cheap to more involved. You usually start with the lower steps and only step up if needed:

  • Antiperspirant with aluminium chloride (step 1): applied to dry skin in the evening, it narrows the sweat glands. Over the counter, cheap, well suited for armpits, hands and feet.
  • Tap-water iontophoresis (step 2): hands or feet are bathed in water through which a weak current flows. Effective for damp hands and feet, but requires regular use.
  • Botulinum toxin/Botox (step 3): injected into the skin, it temporarily blocks (about 4–9 months) the sweat glands. Very effective on the armpits, but costly and to be repeated.
  • Medication or surgery (step 4): tablets that dampen the sweating, or in rare, severe cases a surgical procedure — only after careful medical consideration.
  • Adjust everyday habits: breathable clothing, airy shoes, reduce triggers such as coffee, alcohol and spicy food, reduce stress and maintain a healthy body weight.

Recognise triggers, understand patterns

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How brite helps you with excessive sweating

Excessive sweating has many possible causes — from a predisposition to a medication. Whoever records when and where they sweat and which preparations they take gives the doctor the decisive clues. brite makes that easy.

  • Health history — document sweating episodes, affected spots and possible triggers (stress, heat, menopause) over time and bring it as an overview to your appointment. Track your history
  • Interaction check — checks whether one of your medications (e.g. certain antidepressants such as SSRIs or opioids) promotes the sweating. Check now
  • Intake reminder — if an antiperspirant or prescribed medications need to be applied regularly, brite reliably reminds you. Set up a reminder
  • Digital medication plan — all medications clearly in one place for your GP and dermatology. Go to the medication plan
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FAQ: Common questions about excessive sweating

Excessive sweating (hyperhidrosis) is when the body produces clearly more sweat than would be needed to regulate temperature — for example wet hands, sweat-soaked clothing or dripping armpits without exertion or heat. What also matters is whether the sweating is a heavy burden for you in everyday life or socially.
Primary hyperhidrosis is usually confined to a local area (hands, feet, armpits), often begins as early as adolescence and has no recognisable underlying condition. The secondary form occurs all over the body, frequently begins anew in adulthood and is triggered by a condition or a medication. This distinction determines the investigation and treatment.
Yes, this is a common and often overlooked cause. In particular certain antidepressants such as SSRIs (for example Sertraline) and opioids (strong painkillers) can trigger increased sweating, as can some thyroid and diabetes medications. But never stop a medication on your own — discuss the suspicion with your doctor.
Treatment usually proceeds step by step: first an antiperspirant with aluminium chloride, then tap-water iontophoresis for hands and feet, next botulinum toxin (Botox) mainly for the armpits, and only last of all tablets or, in severe cases, surgery. Which step fits depends on the location and extent of the sweating.
Antiperspirants are cheap and available without a prescription. Iontophoresis devices involve a one-off purchase cost or are used at the practice. Botox on the armpits can cost several hundred euros per session and has to be repeated. Whether and to what extent the health insurer covers anything depends on the severity and the particular insurer — it is best to clarify this in advance.
Sweating at night is often harmless, for example due to bedclothes that are too warm or the menopause. Newly appeared, marked night sweats together with fever, unintended weight loss and severe fatigue (B symptoms) should, however, be investigated by a doctor promptly, as rarely serious conditions can be behind them.
Yes. During the menopause the hormonal changes frequently lead to hot flushes and sweating episodes, often also at night. An overactive thyroid can also trigger increased sweating. With new, generalised sweating, a blood test of the thyroid values is therefore often part of the investigation.
Normal deodorants mainly mask the odour but barely reduce the amount of sweat. Against the amount, antiperspirants with aluminium chloride work by temporarily narrowing the sweat glands. They are best applied to dry skin in the evening. If that is not enough, there are further treatment steps.
According to current knowledge, the external use of aluminium chloride in antiperspirants is considered acceptable; there is no proven link with serious conditions. Some people get skin irritations — this can often be reduced by applying it in the evening and using the right dose. If you are unsure, speak to your doctor.

10. Related topics

Night sweats Hot flushes Overactive thyroid Menopause Sertraline

Sources

  1. gesundheitsinformation.de (IQWiG): Excessive sweating (hyperhidrosis). gesundheitsinformation.de
  2. German Dermatological Society (DDG): Guideline on the definition and treatment of primary hyperhidrosis. derma.de
  3. Institute for Quality and Efficiency in Health Care (IQWiG). iqwig.de

This article is for general information and does not replace medical advice, diagnosis or treatment. If sweating occurs suddenly together with chest pain, tightness or shortness of breath, please call the emergency number 112 without delay.