Sweating is the body’s natural way of cooling off. The normal physiological process of sweating involves the nervous system, which triggers the sweat glands when the body temperature rises. Sweating can also result from nervousness or anxiety, in which case it most commonly occurs on the palms of the hands and in the armpits.

Excessive sweating due to hyperhidrosis can arise as a stand-alone condition or be related to a secondary medical condition, such as thyroid disease, cardiovascular conditions, or menopause.

Read on to learn about causes of hyperhidrosis.

Common Causes

Hyperhidrosis is classified as either primary focal hyperhidrosis or secondary generalized hyperhidrosis, both of which have numerous individual possible causes.

Primary Focal Hyperhidrosis

Primary focal hyperhidrosis involves sweating in one or more “focal” areas of the body, usually on the palms of the hands, under the arms, or the soles of the feet. Focal hyperhidrosis may also affect the face and/or scalp.

There are several causes of primary focal hyperhidrosis, including:

  • Primary idiopathic hyperhidrosis: Idiopathic means the disease has an unknown cause or mechanism of origin. Most cases of primary hyperhidrosis are idiopathic.Frey’s syndrome: A rare neurological disorder also called gustatory sweatingOther neurologic conditions: Examples include spinal injuries and miscellaneous conditions of the nervous system.

Secondary Generalized Hyperhidrosis

Secondary generalized hyperhidrosis refers to sweating that occurs all over the body and may include night sweats (sweating while asleep). It usually develops in adulthood and is caused by a secondary or underlying disorder affecting any of several systems in the body or by other factors:

Endocrine

  • Hyperthyroidism
  • Diabetes
  • Hyperpituitarism
  • Menopause (hot flashes)
  • Pregnancy
  • Pheochromocytoma (a small tumor of the adrenal gland)
  • Carcinoid syndrome (a rare disorder triggered by an altered immune system response)
  • Acromegaly (an abnormality of the pituitary gland, which produces too much growth hormone and is characterized by the development of an oversized face, hands, and feet)

Neurological

  • Parkinson’s disease
  • Stroke (cerebral vascular accident)
  • Spinal cord injury

Malignancy

  • Hodgkin’s disease
  • Myeloproliferative disorders (a group of slow-growing blood cancers)

Cardiovascular-Related

  • Shock
  • Heart failure
  • Stroke

Side Effects of Medications

  • Anticholinesterases used to treat Alzheimer’s disease
  • Antidepressants including Prozac (fluoxetine), Sinequan (doxepin), Norpramin (desipramine), Pamelor (nortriptyline), and Effexor (venlafaxine)
  • Anxiolytic drugs used to treat anxiety
  • Asthma inhalers such as albuterol
  • Depo-Provera birth control pills
  • Insulin used to manage diabetes
  • Methadone used to treat heroin addiction
  • Migraine medications such as Triptan (rizatriptan) and sumatriptan
  • Non-steroidal anti-inflammatory drugs like Celebrex (celecoxib)
  • Opioids like Vicodin (hydrocodone) and Oxycontin (oxycodone)
  • Salagen (pilocarpine) used to treat glaucoma
  • Propranolol used to treat angina and hypertension
  • Testosterone
  • Thyroid-regulating drugs

Other Factors

  • Alcohol withdrawal
  • Fever
  • Infection (such as malaria, HIV, or tuberculosis)
  • Obesity
  • Opiate withdrawal
  • Respiratory failure
  • Toxicity from alcoholism or substance abuse

Genetics

In primary focal hyperhidrosis, sweating usually starts during childhood, which suggests it may be genetic. A 2019 review of 20 published studies found a wide range of positive family history—from 5.7% to 65%.

The study authors noted primary focal hyperhidrosis appears to have an autosomal dominant pattern, meaning only one copy of the gene for the disease is required for it to manifest. In addition, the gene can be passed along by either the male or female parent, and both sexes are at equal risk of inheriting hyperhidrosis.

Weight

A common cause of secondary hyperhidrosis is extra body weight and obesity. This is likely due to body heat becoming trapped by adipose tissue, kicking off the body’s natural cooling response, and causing excessive perspiration.

A 2019 study published in the Journal of the American Academy of Dermatology assessed the link between body mass index (BMI) and hyperhidrosis. The study included nearly 2.8 million teenagers. It found higher rates of hyperhidrosis in obese individuals than in those who were underweight. In addition, the study authors noted the risk of hyperhidrosis increased for each BMI unit above the normal weight threshold. 

Cardiovascular

Several factors related to normal cardiovascular function overlap with hyperhidrosis. The same mechanism that triggers sweating in hyperhidrosis causes an increase in heart rate and blood pressure.

BMI is a dated, flawed measure. It does not take into account factors such as body composition, ethnicity, sex, race, and age. Even though it is a biased measure, BMI is still widely used in the medical community because it’s an inexpensive and quick way to analyze a person’s potential health status and outcomes.

The sympathetic nervous system, which activates the fight-or-flight response, plays a role in hyperhidrosis. The fight-or-flight response causes an increase in heart rate and blood pressure, which leads to excessive sweating.

In addition, a 2016 study assessed post-exercise blood pressure and recovery heart rate in people with hyperhidrosis and those without and found people with secondary generalized hyperhidrosis of unknown origin had a significantly impaired blood pressure recovery and decreased heart rate recovery after exercise.

People with focal hyperhidrosis may have abnormal heart rate patterns, according to a study published in the journal European Neurology that compared 63 people with focal hyperhidrosis to a group of healthy control subjects.

A Word From Verywell

There are many factors involved in the cause of the different forms of hyperhidrosis, however, perhaps the most important thing to keep in mind is that the condition is treatable. You can explore resources that provide education and support to those who have hyperhidrosis. While hyperhidrosis can be an embarrassing condition, it doesn’t have to be one that takes over a person’s life.

Frequently Asked Questions

  • Is there a cure for hyperhidrosis?
  • No, there isn’t a permanent cure for primary, or focal, hyperhidrosis, though some people find the condition goes into remission in early adulthood. Secondary hyperhidrosis may abate if the underlying cause of the condition can be addressed. For example, excessive sweating due to obesity may lessen when extra pounds are lost.
  • How common is primary hyperhidrosis?
  • According to a 2016 survey published in the Archives of Dermatological Research, 4.8% of the U.S. population—around 15.3 million people—has primary hyperhidrosis, most between ages 18 and 39. This statistic may not be entirely accurate, as other research has found people often are reluctant to report excessive sweating to a doctor and many are never diagnosed.
  • How do I know if I have primary or secondary hyperhidrosis?
  • A key difference between the two types is the location of excess sweating. Primary hyperhidrosis typically affects the soles of the feet, the palms of the hands, the underarms (axillary hyperhidrosis), or the face and scalp. People with secondary hyperhidrosis sweat all over. For instance, the night sweats common during menopause are considered secondary hyperhidrosis.

No, there isn’t a permanent cure for primary, or focal, hyperhidrosis, though some people find the condition goes into remission in early adulthood. Secondary hyperhidrosis may abate if the underlying cause of the condition can be addressed. For example, excessive sweating due to obesity may lessen when extra pounds are lost.

According to a 2016 survey published in the Archives of Dermatological Research, 4.8% of the U.S. population—around 15.3 million people—has primary hyperhidrosis, most between ages 18 and 39. This statistic may not be entirely accurate, as other research has found people often are reluctant to report excessive sweating to a doctor and many are never diagnosed.

A key difference between the two types is the location of excess sweating. Primary hyperhidrosis typically affects the soles of the feet, the palms of the hands, the underarms (axillary hyperhidrosis), or the face and scalp. People with secondary hyperhidrosis sweat all over. For instance, the night sweats common during menopause are considered secondary hyperhidrosis.