Botulinum Toxin Injections for the Treatment of Hyperhidrosis

Botulinum Toxin Injections for the Treatment of Hyperhidrosis or Excessive Sweating

Botulinum toxin injections are an effective method for reducing localised excessive sweating, or hyperhidrosis. During the procedure, small doses of botulinum toxin are injected into the skin, temporarily reducing the transmission of nerve impulses to the sweat glands. As a result, sweating in the treated area is significantly reduced. The American Academy of Dermatology lists botulinum toxin injections as one of the treatment options for hyperhidrosis affecting the underarms, palms, soles of the feet and, in selected cases, the face.

In everyday language, this procedure is often referred to as “Botox for sweating” or “Botox for hyperhidrosis”. The more medically accurate term is botulinum toxin type A injections for the treatment of hyperhidrosis. Botox® is one of the brand names of botulinum toxin preparations.

Botulinum toxin injections for the reduction of hyperhidrosis are performed in the underarm and palm areas. The maximum effect usually develops within approximately three weeks and, on average, lasts for 4–6 months.

What is hyperhidrosis?

Hyperhidrosis is excessive sweating that exceeds the body’s physiological need to regulate temperature. It can cause not only physical discomfort but can also significantly affect everyday life, professional activities, clothing choices, social interactions and overall well-being.

Excessive sweating most commonly affects:

  • underarms;

  • palms;

  • soles of the feet;

  • face and scalp.

A distinction is made between primary focal hyperhidrosis, which is not caused by another medical condition, and secondary hyperhidrosis, which may be associated with certain diseases, hormonal changes or medication use. Therefore, in cases of severe or suddenly developing sweating, it is important first to determine the possible cause.

How does botulinum toxin reduce sweating?

Sweat gland activity is stimulated by signals from the nervous system. Botulinum toxin temporarily inhibits the transmission of nerve signals to the sweat glands in the treated area, thereby reducing sweat production specifically at the injection site.

The procedure does not stop sweating throughout the whole body and does not interfere with the body’s natural thermoregulation overall. Its effect is local and temporary. Nerve signal transmission gradually recovers over time, so the procedure can be repeated once the effect diminishes.

Who may benefit from botulinum toxin treatment for hyperhidrosis?

The procedure may be considered if excessive sweating:

  • regularly causes visible sweat marks on clothing;

  • interferes with work, sport or social situations;

  • makes it difficult to grip objects or work with the hands;

  • causes significant discomfort and a frequent need to change clothes;

  • is not adequately controlled with antiperspirants or other conservative methods.

According to the recommendations of the International Hyperhidrosis Society, botulinum toxin injections are one of the treatment options for patients with primary focal hyperhidrosis, especially when simpler methods have not provided sufficient benefit.

Botulinum toxin injections for underarms

Underarm hyperhidrosis is one of the most commonly treated forms of hyperhidrosis. The injections are administered at multiple points in the sweating area so that the botulinum toxin acts evenly on the relevant sweat glands.

The American Academy of Dermatology states that reduced sweating becomes noticeable in most patients within approximately 7–10 days, while the effect in the underarm area may last for several months. The average duration of effect is 4–6 months.

Botulinum toxin injections for palms

Palmar hyperhidrosis can make writing, working with a computer, handling tools or documents, as well as everyday social contact, more difficult.

Botulinum toxin can also significantly reduce sweating in the palms. Because the palms contain many nerve endings, the procedure can be more sensitive than treatment in the underarm area. If necessary, the specialist may use pain-relieving methods. In rare cases, temporary weakness of the hand muscles may occur after the procedure.

How is the procedure performed?

Before the procedure, the doctor assesses the patient’s symptoms, severity of sweating, general health, medications being taken and checks for possible contraindications.

The skin is disinfected and several small botulinum toxin injections are administered into the selected area using a fine needle.

A botulinum toxin treatment visit usually lasts approximately 20–30 minutes. After the procedure, mild redness, swelling or tenderness may occur at the injection sites, but patients can usually return to their daily activities shortly afterwards.

When does botulinum toxin start working?

The effect is not immediate. A reduction in sweating is usually noticed within the first few days or around one week after the procedure. The maximum effect is generally expected within approximately three weeks and lasts on average 4–6 months. The individual result and duration of effect may vary.

As sweating gradually returns, the procedure can be repeated after assessment by a specialist.

How to prepare for the procedure?

Before botulinum toxin injections, it is important to inform the doctor about all medical conditions, previous botulinum toxin procedures, prescription and over-the-counter medicines, dietary supplements, as well as pregnancy or plans to become pregnant. Certain medications may increase the risk of bruising or other side effects.

Medication should not be stopped independently before the procedure. Any necessary changes should always be discussed with a doctor.

Possible side effects and precautions

Botulinum toxin injections are generally well tolerated; however, as with any medical procedure, side effects may occur. The most common are temporary reactions at the injection site, such as redness, tenderness, slight swelling or bruising. In the case of palm treatment, temporary muscle weakness may also occur. Very rare but serious botulinum toxin complications are associated with the spread of toxin effects beyond the injection area.

Suitability for the procedure should be assessed particularly carefully in cases of neuromuscular disease, infection at the injection site, pregnancy or breastfeeding, as well as when taking certain medications.

When is additional examination necessary?

If excessive sweating develops suddenly, begins in adulthood, is pronounced at night or affects the whole body, a medical consultation is recommended to rule out secondary hyperhidrosis. Excessive sweating can also be caused by other health conditions or medications. In such cases, the primary treatment goal may be to identify and treat the underlying condition or trigger rather than only reducing sweating.