While doctors don’t know why excessive sweating starts, the most likely cause is genetics. Medical Scientists have successfully linked hyperhidrosis to an over-activity in the sympathetic nervous system, which is genetically determined.
In cases of palmar hyperhidrosis (hand sweating), the responsible sympathetic ganglia that receive the signal for that abnormal activity are located within the upper part of the chest cavity. In cases of plantar hyperhidrosis (foot sweating), the responsible sympathetic ganglia that receive the wrong signal are located within a section of the lumbar sympathetic chain. This is a simplified way of explaining the complex anatomical and neurological basis for excessive local hyperhidrosis (Excessive sweating of the Hands, Feet & Armpits).
Further explanation of the problem can be divided into two categories:
- Generalized hyperhidrosis – Over the entire body.
- Focal (Localized) hyperhidrosis – Focused in one area. (Hands, Feet, Face, Armpit)
Causes of Excessive Sweating – Generalized Hyperhidrosis
In cases with generalized hyperhidrosis, excessive sweating can appear in most parts of the body. It can happen on the face, body, and extremities. In those cases, most of the patients do have some other systemic problems such as obesity, febrile illnesses, some sort of neoplastic disease (cancers), or some endocrinological disorders (thyroid glands, etc).
A search for a specific reason to explain excessive sweating in general can be long. A cause cannot be found in every case, in which case the diagnosis of idiopathic hyperhidrosis can be applied to those cases. Idiopathic meaning “unknown.” Cases of generalized hyperhidrosis usually appear in the adult population, where cases of focal hyperhidrosis (hands, feet, armpits) usually start at a younger age.
It is not uncommon to hear mothers call about their infants who suffer from excessive sweating. This is more bothersome to the parents than the child at that time. It is usually later in life, when the child has more social and functional needs such as school, that hyperhidrosis can become a serious and bothersome issue.
Another common situation that is asked about very often, is the manifestation of upper body sweating in elderly patients, especially elderly women. This could present a unique situation where aging, hormonal changes, weight, and lack of activity can contribute to this particular type of sweating. Even though it is a common question, a specific cause cannot be identified.
As a result, an effective treatment is not always easy to find. Another common location of excessive sweating that patients mention is hairline sweating and scalp sweating. It is described by patients as if they just got out of the shower. This is another form of sweating which is not responsive to current surgical treatment. This would be more closely associated with facial hyperhidrosis.
Causes of Excessive Sweating – Focal Hyperhidrosis
In focal hyperhidrosis, there are specific sites where excessive sweating occurs. The most common areas of the body are the hands, armpits, and feet. In these cases of focal hyperhidrosis, the most likely explanation is a genetic trait.
We know that in most studies, a genetic connection was shown in about 50% to 60% of the cases. Even though the genetic connection is very well established genetic manipulation for the purpose of treatment is still a very long ways off. Dr. Reisfeld believes one day this will be a key element in the treatment of focal hyperhidrosis.
This sympathetic chain innervates the glands (supplies with nerve endings), known as the apocrine and eccrine glands, responsible for perspiration throughout the entire body. The eccrine sweat glands are mainly concentrated in the palms of the hands and soles of the feet. In most cases, the hands and feet are affected. To a lesser degree, the face and armpits (axilla) regions are affected. Another possible manifestation of the hyperactive sympathetic activity is facial blushing.
It used to be a common thought that excessive hand sweating was caused by an overactivity of the thyroid gland, but over the years this was disproved. Another theory was that patients who suffered from anxiety problems would have excessive hand sweating. This was also proven to be wrong, as patients can have severe palmar hyperhidrosis (hand sweating) even in the most relaxed settings.
Having said that, it is still true that anxiety and or socially unpleasant situations can add to this, just as they would affect a person without hyperhidrosis. This is because of the secretion of sympathetic-like materials/hormones (mediators) from different organs in the body.
Sometimes people sweat heavily because of other illnesses, such as hyperthyroidism, psychiatric disorders, menopause, obesity, and some medications. These causes must first be ruled out before Primary Hyperhidrosis can be diagnosed. Dr. Reisfeld speaks with potential candidates for the procedure over the phone or in person to review their condition and advise them of their best options.
Sweat can occur in many different areas on the body. Most commonly, focal hyperhidrosis occurs on the palms of the hands. In such cases, this condition is known as Palmar Hyperhidrosis. But hyperhidrosis is not just limited to the hands. It can also occur on the face, the soles of the feet (plantar), and in the armpits (axillae).
Regardless of where it occurs, excessive sweating presents an incredible difficulty to those living with the condition. When the act of shaking hands presents a problem, business and day-to-day life can become very uncomfortable. Many patients report that they are embarrassed to hold the hands of those they love and those they are closest to.
Some patients report that the sweat prevents them from being as sociable and intimate as they would like to be, as they are forced to hide in the shadow of hyperhidrosis. Other problems occur, such as smeared ink when writing, or an inability to use electronic devices such as keyboards and computers. Driving with excessive hand sweating can become hazardous as well.
There are several cases of broken ankles due to excessive foot sweating causing slips from shoes or sandals. Hyperhidrosis can deeply affect people socially and functionally in their everyday lives. Thankfully, there is a permanent surgical solution for the condition.
Hyperhidrosis is a constant challenge:
By saying this we do not mean that it happens 24 hours a day, but we’re referring to the fact that it happens on a daily basis. For example, the vast majority of patients who suffer from hyperhidrosis have dry hands and feet at night. Very few patients will describe excessive sweating during night time.
The explanation for this is that during night time the sympathetic activity in the body declines to a minimal level. Subsequently, blood pressure and pulse rate are also down. Constant sweating also means that it happens in winter as well as in summer. If the patient is afflicted with hyperhidrosis, then it becomes a constant issue.
In rare occasions, a small number of patients will describe reduction in the amount of excessive sweating as they grow older. This can happen due to some unknown genetic changes.
Is the anatomy of the sympathetic chain the same for everyone?
No, although the sympathetic chain is similar in most people, in some cases it may be different. Only very experienced surgeons will be able to identify the abnormality and solve any issues presented.
Does diabetes have anything to do with hyperhidrosis?
There is no correlation between diabetes and hyperhidrosis, but patients who have diabetes might also have hyperhidrosis. Uncontrolled diabetes can produce generalized body hyperhidrosis, which is different from focal hyperhidrosis (armpits, hands, feet). View our complete page on hyperhidrosis and diabetes.
Do you have questions about Hyperhidrosis Symptoms and Causes?
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Other topics of interest:
- Sweaty Hands
- Sweaty Feet
- Armpit Sweating
- What is ETS – Endoscopic Thoracic Sympathectomy
- Details of the surgery
- Patient Success Stories
- Frequently asked hyperhidrosis questions
Do you have any sweat related questions that were not answered here? Would you like to speak with Dr. Reisfeld to answer those questions? To learn more about what we can do for you, contact The Center for Hyperhidrosis by contacting our office.
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