Sweaty armpits: causes and practical care advice

20.05.2026

Underarm sweating is a natural physiological process that helps regulate body temperature. Sweat glands are found across the body – typically about 2 to 5 million, depending on the individual. For most people, the underarms play an important role in this temperature regulation. For others, however, underarm sweat can become excessive and difficult to manage in everyday life.

In this article, we explain why underarm sweating occurs, and how underarm sweat relates to body odour and how to manage both with the right care.

Why do armpits sweat so much?

To better understand why you sweat in the armpits, it helps to know a bit about sweat glands. The body has millions of sweat glands, but they are not evenly distributed. Even though the underarms contain relatively few sweat glands compared to other areas, sweating here can feel especially uncomfortable.

This is partly due to the type of sweat glands found in the underarms, and because sweat does not evaporate easily when the arms are held close to the body.

There are two main types of sweat glands:

Eccrine glands produce sweat made mainly of water and salts. They are found across the whole body, with the highest density on the hands, feet, and forehead.

Apocrine glands are mainly located in hairy areas such as the armpits. They produce a thicker sweat containing proteins and lipids. While this sweat is odourless at first, it can lead to body odour when underarm bacteria break it down. This is why sweating armpits are often linked to stronger body odour.

Apocrine glands typically become active during puberty, which helps explain why underarm sweating and body odour often increase during the teenage years.

Sweating can be influenced by:

Climate and physical activity:
Hot environments and sport activities increase sweat production to help regulate body temperature.
Hormonal changes:
Hormones such as oestrogen and testosterone affect sweat gland activity. Changes during puberty, the menstrual cycle, and menopause can change sweating patterns.
Emotional factors:
Stress and anxiety can activate sweat glands via the sympathetic nervous system, causing “stress sweat,” for example before an important presentation or during a job interview.

Medical conditions:
Conditions such as hyperhidrosis, hyperthyroidism, diabetes, infections, and certain medications can lead to increased sweating.

The results can be life-changing for my patients suffering from excessive sweating – it’s a solution that gives them control and significantly improves their quality of life.

Stine Marie Andersen | Board-certified Dermatologist, Associate professor MD Ph.D, Denmark

The connection between underarm sweat and body odour

Sweat itself is odourless. The smell develops when sweat interacts with bacteria on the skin, leading to smelly armpits. The bacteria on the skin break down the sweat resulting in body odour.

It is important to remember that everyone’s skin microbiome is unique. The skin microbiome consists of many types of occurring bacteria, and its composition varies from person to person. This is why body odour can smell different from one individual to another.

How to stop sweaty armpits effectively

Many people experience sweaty and smelly armpits and often search online for answers such as “how to stop armpit sweat” or “how to stop sweating underarms”. The reality is that no product can completely stop sweating but when the goal is to reduce underarm sweat and odour, extra-effective antiperspirants can be the solution.

Aluminum Chloride is a widely recognised ingredient as a first‑line treatment for excessive underarm sweat. When applied to the skin, it temporarily blocks sweat glands, helping reduce the amount of sweat that reaches the skin’s surface. This also helps limit the moist conditions where odour-causing bacteria tend to thrive.

Aluminum Chloride is the active ingredient in all Perspirex products. So, if you have ever searched for “how to reduce armpit sweat,” “how to get rid of underarm odour,” or “how to stop smelly armpits,” Perspirex may offer an effective solution to your sweat problem by reducing underarm sweat and odour.

Perspirex Comfort

Perspirex Comfort is an extra-effective antiperspirant for intense sweating with a skin care system to minimise the risk of skin irritation. It has a clinically proven protection effect against sweat and odour for up to 5 days.

How to get rid of underarm odour and sweat: tips and care

Use an extra‑effective antiperspirant: Perspirex range

Excessive underarm sweating can be uncomfortable and impact daily life. Extra‑effective antiperspirants, such as the Perspirex range, are designed to help control armpit sweat and support long‑lasting dryness.

Antiperspirants act directly on the sweat glands by forming a temporary gel plug, which helps reduce underarm sweat throughout the day.

For maximum effectiveness, apply an extra-effective antiperspirant like Perspirex at night when the sweat glands are less active and sweating is minimal. A review published in the Journal of the American Academy of Dermatology highlights Aluminum Chloride as the most effective first‑line option for controlling excessive sweating.

Lifestyle habits that support sweat and odour control

Lifestyle factors alone cannot stop sweating entirely, but they can support a routine focused on how to reduce armpit odour and improve overall comfort.

Hydration: Staying well hydrated supports efficient temperature regulation and can help your body manage perspiration more effectively.

Body weight: Maintaining a healthy body weight can help regulate body temperature and reduce excessive armpit sweat.
Dietary triggers: Spicy foods, caffeine, and alcohol can stimulate sweat glands and may increase underarm sweat.
Stress management: Stress can contribute to smelly armpits and stress‑induced sweating. Techniques such as deep breathing, meditation, or short breaks can help control armpit sweat.

Care for your underarms, hands, and feet

Maintaining healthy skin is important for comfort, odour control, and supporting the effectiveness of antiperspirants for underarm sweating.

Gentle cleansing: Use mild cleansers to remove sweat and bacteria that can contribute to underarm odour and smelly armpits, while protecting the skin barrier.
Correct way of application: Apply Perspirex to clean, dry, and unbroken skin at night when the sweat glands are least active. Proper application helps reduce underarm sweat, control odour, and minimize discomfort.
Underarms – shaving carefully: Remove hairs and moisturize afterwards to prevent irritation. To reduce sensitivity and help prevent armpit odour, avoid shaving for two days before using Perspirex.

Healthy skincare routines can help reduce armpit odour and support long‑lasting dryness.

Choosing the right solution for sweaty hands

Aluminum Chloride is a doctor-recommended active ingredient for excessive sweating and is widely used as a first line of treatment option for excessive sweating. It works by forming temporary gel plugs within the sweat ducts, which reduces the amount of sweat that reaches the surface of the skin.

Aluminum Chloride is the active ingredient used in all Perspirex products, including Perspirex Hand. So, if you experience sweaty hands, Perspirex Hand is a valuable solution.

To further support this, a user study was conducted in which 88% of users felt the product reduced their hand sweating.

How antiperspirants for hands work

Antiperspirants for hands work in the same way as underarm antiperspirants: by temporarily blocking sweat glands. The active ingredient in Perspirex Hand is Aluminum Chloride, a doctor‑recommended active ingredient for excessive sweating.

When Aluminum Chloride comes into contact with sweat, it forms a temporary gel plug in the sweat duct. This reduces the amount of sweat that reaches the surface of the skin. This gel plug is resistant to showering and swimming but is naturally dispelled over a few days.

This mechanism makes Aluminum Chloride‑based antiperspirants an effective solution for sweaty palms.

How to use Perspirex Hand correctly

Perspirex Hand is formulated as a clear, fast-absorbing liquid. When applied correctly, it provides reliable protection against palms sweating for several days.

To ensure full protection and minimise the risk of skin irritation, Perspirex Hand must be applied correctly.

Apply a thin film of Perspirex Hand at night before going to bed to unbroken and completely dry. If necessary, use a hairdryer on a cool setting to ensure dryness before application. Be careful not to touch your eyes if you have product on your fingers.
Let it dry and work during the night when the activity of the sweat glands is lower.
Wash off in the morning with soap and water.
Reapply every 3 days or as needed.

When using Perspirex Hand for the first time, we recommend applying it for 7 consecutive nights. If you experience skin irritation, apply less and skip the following night. Maintain protection by applying every 3 days, or as needed.