How can you sweat less?

Perspiration is mainly regulated by the eccrine glands, which are activated in response to an increase in body temperature, and by the apocrine glands, which are more sensitive to emotional stimuli such as stress. Certain everyday factors can intensify their activity. Heat, non‑breathable clothing, or poor moisture wicking promote the activation of eccrine glands, which then increase their output in an attempt to cool the body down. In contrast, natural fabrics such as cotton or linen facilitate the evaporation of sweat, thereby limiting the overheating signals sent to the nervous system and, indirectly, the production of sweat.

Diet and nutrition also play a significant role. Spicy foods, alcohol, or caffeine can stimulate the sympathetic nervous system, leading to an increase in sweating. Similarly, stress and anxiety preferentially activate the apocrine glands via the release of adrenaline, which explains why some episodes of sweating occur independently of ambient temperature. Monitoring one’s diet and trying to relax can therefore help modulate perspiration. Finally, showering after physical exertion, thoroughly drying areas prone to sweating, and changing clothes regularly help limit the accumulation of sweat on the skin’s surface.

Without blocking perspiration, these simple measures help you live better with it.

In cases of localized sweating, for example in the armpits, on the hands, feet or on the face, antiperspirants are generally the first option.

Unlike deodorants, which act primarily on odors, antiperspirants aim to directly reduce the production of sweat. Their effectiveness relies mainly on the presence of aluminum salts, which are able to form temporary plugs inside the sweat ducts. This partial obstruction limits the flow of sweat to the surface of the skin, without completely blocking the function of the glands. This mechanism acts mainly on the eccrine glands, which are responsible for most perspiration. Their effectiveness is well established in mild to moderate forms of localized hyperhidrosis, particularly in the underarms, but also on the palms of the hands and the soles of the feet, using formulations adapted to these areas.

The use of aluminum salts is, however, a subject of debate. Their ability to reduce sweating is well documented, but questions remain about their cutaneous absorption, their passage into the bloodstream, and their long-term effects. To date, the available data do not allow any confirmed risk to be established under usual conditions of use, but this uncertainty may encourage caution.

Less well known to the general public, iontophoresis is nonetheless an interesting option for reducing excessive sweating, particularly on the hands and feet. This technique consists of passing a low-intensity electric current through the skin, generally via water baths in which the areas to be treated are immersed. Although its mechanism of action is not fully understood, several hypotheses have been proposed: temporary obstruction of the sweat ducts, modulation of local nerve activity, or changes in the skin environment that would limit sweat secretion.

In practical terms, treatment begins under the supervision of a healthcare professional, in order to learn how to use the device correctly and adjust the settings. Each session lasts about 20 minutes, during which the hands or feet are placed in trays filled with water. At the start, sessions are relatively frequent, often 2 to 3 times per week, until a visible improvement is achieved. Once sweating is reduced, weekly maintenance sessions, or sometimes every two weeks, help maintain the results. After appropriate training, it is entirely possible to carry out the sessions at home using a dedicated device.

The efficacy of iontophoresis is well documented, with reductions in sweating that can exceed 80% after several sessions, and an effect that persists over time if the treatment is continued on a regular basis.

Side effects are generally mild and temporary, such as tingling, a moderate burning sensation, or redness. In some cases, the skin may become dry or slightly irritated, which can be managed by spacing out treatment sessions or applying a moisturizing care product. However, iontophoresis is contraindicated for certain individuals, particularly in cases of pregnancy or in those who wear a cardiac pacemaker.

Iontophoresis can be viewed as an intermediate solution for excessive sweating : more effective than antiperspirants but less invasive than medical procedures.

Botulinum toxin, produced by the bacterium Clostridium botulinum, is now regarded as one of the most effective options for reducing localized excessive sweating. Its mechanism of action is well understood: it blocks the release of acetylcholine, a neurotransmitter that is essential for activating the sweat glands. Under normal conditions, this nerve signal triggers sweat production in response to heat or stress. By inhibiting this transmission, botulinum toxin temporarily prevents stimulation of the glands, which greatly reduces sweat production in the treated areas.

Injections must be performed by a healthcare professional, using very fine needles. The protocol varies depending on the area: around fifteen injections per armpit may be required, and up to several dozen for the hands. The session lasts on average about twenty minutes, and a topical anesthetic cream can be applied beforehand to improve comfort. The effectiveness of this technique has been confirmed by several clinical studies.

The effects are not immediate but generally appear within a few days, with maximal benefit observed after several weeks. The results typically persist for an average of 6 to 7 months, after which the activity of the sweat glands gradually resumes, requiring additional injections to maintain the effect. Adverse effects are most often mild and temporary: pain at the injection site, redness, swelling, and, in some cases, slight muscle weakness or headaches.

Finally, it is important to be aware of certain precautions. Botulinum toxin injections are contraindicated in pregnant or breastfeeding women, as well as in individuals with neuromuscular diseases, due to its effect on nerve transmission. More broadly, it is essential not to inhibit sweat glands over too large an area, because perspiration plays a key role in thermoregulation. When properly supervised, however, this technique is a good option for localized and treatment-resistant forms of excessive sweating.

When sweating is generalized, medication-based treatments may be considered.

The most commonly used are anticholinergics, which work by blocking the action of acetylcholine, the neurotransmitter involved in activating the sweat glands. Unlike topical solutions or localized injections, these medications have a systemic effect, which makes it possible to reduce sweating in multiple areas of the body at the same time.

However, this systemic action is often accompanied by adverse effects, related to the role of acetylcholine in numerous physiological functions. Patients may experience dry mouth, reduced tear production, digestive disturbances, and even difficulty concentrating. These effects limit their use, particularly over the long term, and explain why these treatments are generally reserved for moderate to severe forms of hyperhidrosis, when other options prove insufficient.

In the most severe and treatment-resistant forms of hyperhidrosis, surgical options may be considered, particularly when topical and medical treatments have not provided sufficient improvement. The best-known technique is thoracic sympathectomy, mainly indicated in cases of excessive sweating of the hands and armpits. Its goal is to act directly on the nervous system responsible for activating the sweat glands.

The procedure consists of interrupting a portion of the sympathetic nerve, located along the spine, which transmits the signals that trigger sweating. It is performed under general anesthesia, most often by thoracoscopy, a minimally invasive technique that allows a camera to be introduced into the chest through a small incision in the armpit area. Once the nerve is located, it is cut over a short distance. This procedure is generally quick, and the results are often immediate and long-lasting, with a clear reduction, or even disappearance, of sweating in the targeted areas.

However, despite its effectiveness, thoracic sympathectomy remains a treatment of last resort, due to its invasive nature and potential side effects.

The most significant one is compensatory hyperhidrosis, which corresponds to an increase in sweating in other areas of the body, such as the back or chest. This phenomenon can be more or less pronounced depending on the individual. Therefore, this procedure requires a thorough evaluation and discussion with a healthcare professional, in order to carefully weigh the expected benefits against the associated risks.

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