What Is Hyperhidrosis?

Overview

Sweating is a normal and efficient biological mechanism that is designed to regulate our body temperature (through a process termed thermoregulation), helping us cool down during periods of extreme heat and exercise. The body uses sweat glands, particularly eccrine glands, to excrete sweat mainly from the axillae (armpits), palms, soles, and face.¹ 

In most people, eccrine sweat gland activity is tightly regulated so that sweat is excreted in the right amount, at the right time, and in the right place. 

However, according to the International Hyperhidrosis Society, the eccrine glands in some people are overactive, causing sweat to be excreted at a quantity that is four to five times higher than normal, or necessary to cool the body down. As a result, people with hyperhidrosis experience profuse sweating for no apparent reason, even at rest, leading to intense feelings of embarrassment, anxiety, and discomfort. 

Causes of hyperhidrosis

The causes of hyperhidrosis sweat depend primarily on its type. Hyperhidrosis is categorised as either primary hyperhidrosis or secondary hyperhidrosis.¹ 

Primary hyperhidrosis often occurs earlier in life, before the age of 25. Primary hyperhidrosis is also referred to as focal hyperhidrosis, which is a chronic skin disorder that is believed to be caused by:

• Genetic mutations (changes in certain genes) inherited from family members 
• Certain foods, for example coffee, chocolate, peanut butter, citric acid, and spices
• Heat
• Emotional stress
• Spinal cord injuries 

On the other hand, secondary hyperhidrosis, or generalised hyperhidrosis, is often caused by:¹ 

• Medical conditions, such as diabetes, Parkinson’s disease, hyperthyroidism (overactive thyroid), and hypoglycaemia (low blood sugar) 
• Medications, such as insulin, dopamine agonists, selective serotonin reuptake inhibitors (SSRIs), and antipsychotics 
• Infections, such as tuberculosis
• Tumours, such as pheochromocytoma (benign tumour in the adrenal glands) and lymphoma (a type of blood cancer)
• Menopause 

Signs and symptoms of hyperhidrosis

Symptoms of hyperhidrosis

The signs and symptoms of hyperhidrosis sweat vary from person to person depending on the severity of the condition. Excessive sweat may have a mild to moderate effect, with symptoms that pose a major challenge in everyday life. 

However, generally speaking, the main symptoms of hyperhidrosis include the following: 

• Sweating through clothes and socks (plantar hyperhidrosis) to the point that they need to be changed regularly 
• Sweat that pools around the back and under the arms (axillary hyperhidrosis) 
• Sweat that drips down the hands (palmar hyperhidrosis), forehead (facial hyperhidrosis), and/or cheeks 

The heavy sweating in focal hyperhidrosis (primary hyperhidrosis) often also occurs bilaterally on both sides of the body (hands and feet) and does not cause night sweats. In contrast, generalised hyperhidrosis (secondary hyperhidrosis), causes night sweats.  

Signs of hyperhidrosis

Hyperhidrosis sweat may also lead to the following signs:

• Itching and inflammation 
• Body odour: Contrary to popular belief, sweat does not have a smell and is in fact, odourless. Sweat only starts to smell bad once bacteria on the skin start to break down certain compounds in sweat 
• Skin changes from excessive moisture from sweat can cause skin maceration, discolouration, paleness, wrinkles, or cracking

Diagnosis

A diagnosis for hyperhidrosis is often provided by a healthcare provider such as a dermatologist by performing a series of tests in the following order:¹ 

• Physical examination and taking a medical history 
• Laboratory tests: These include blood or urine tests to confirm or rule out any underlying medical conditions
• Sweat tests: A healthcare provider might recommend either or both of the following tests to be performed to measure how much sweat the patient’s body produces: 
• Starch-iodine test: The healthcare provider will apply some iodine solution to the area/s with excessive sweat before sprinkling some starch over it. A diagnosis of hyperhidrosis is confirmed if iodine turns dark blue or purple
• Paper test: The healthcare provider will wipe the patient’s sweaty area with a special paper, and will then weigh the paper. A diagnosis of hyperhidrosis is confirmed if the paper is heavy. Typically, the heavier the paper weighs, the more severe the hyperhidrosis is

Management and treatment for hyperhidrosis

The main current hyperhidrosis treatment and management options include:² 

• Lifestyle changes: This involves showering more often and/or wearing breathable clothes. This is effective mainly for those with mild symptoms 
• Aluminum-based antiperspirants: Over-the-counter antiperspirants, such as aluminium chloride hexahydrate, are considered the first-line treatment for those with excessive underarm sweating. They work by decreasing the amount of sweat secreted from sweat glands. Despite their effectiveness, patients may develop side effects, such as skin irritation, and become intolerant to them over time
• Oral medications: The main oral medications that may be recommended include:
• Anticholinergic drugs: People with generalised hyperhidrosis symptoms are often advised to take anticholinergic drugs, such as glycopyrrolate and oxybutynin, alongside aluminium-based antiperspirants as they tend to make them work more efficiently. Unfortunately, anticholinergic drugs may give rise to dry eyes and mouth, urinary retention, and constipation 
• Beta-blockers 
• Antidepressants 
• Clinical-grade cloth wipes: Single-use, premoistened, prescription-strength cloth wipes with glycopyrronium tosylate may help reduce armpit sweating, especially when used daily

If hyperhidrosis sweat does not decrease despite implementing lifestyle changes and/or taking medication, a healthcare provider might recommend further specialised treatment options, such as:^1,3  

• Iontophoresis: This involves placing hands and feet in a tub of tap water. A special device is then used to pass a low electrical current through the water and into the skin, thus blocking the sweat glands temporarily. Iontophoresis is recommended 2-3 times per week for a total of 10-20 minutes per treatment session 
• Botox injections: This involves injecting botulinum toxin into overactive sweat glands, which helps stop sweating for as long as 6-24 months. Despite their effectiveness, botox injections are very expensive and need to be taken every 3-4 weeks for optimal results
• Microwave therapy: This involves placing a high-tech device in areas with excessive sweat, mainly the armpits. The device produces heat (thermal energy) which destroys sweat glands in the axillae permanently, thus stopping underarm sweating for good. The treatment is about 1-hour long

Complications

Because hyperhidrosis causes uncontrollable, profuse sweating at any time, place, and for no apparent reason, it can lead to a wide range of complications including:¹ 

• Severe psychological and/or emotional distress 
• Social embarrassment 
• Withdrawal from social activities, such as shaking hands
• Work and/or school-related disability
• Skin infections 
• Severe compensatory sweating: Best described as increased sweating in the back, chest, and abdomen following invasive hyperhidrosis treatments, mainly after a sympathectomy. Sympathectomy is a surgical treatment that involves cutting specific nerve ganglia (T1-T4) to stop facial, palmar, and/or armpit sweating permanently ⁴ 

FAQs

How can I prevent hyperhidrosis?

The type of hyperhidrosis a patient has determines whether or not it can be prevented. 

Unfortunately, focal hyperhidrosis cannot be prevented as it has a strong genetic element, whilst generalised hyperhidrosis can be prevented, at least in some cases. 

The following tips may help prevent generalised hyperhidrosis:¹ 

• Living a healthy, active lifestyle to prevent metabolic and neurological diseases that may trigger hyperhidrosis 
• Lowering stress levels 
• Avoiding drug overuse, especially when taking prescription drugs 
• Staying hydrated and keeping cool, especially when exercising in hot conditions 

How common is hyperhidrosis?

This condition is quite common. Although the exact number of people affected with hyperhidrosis worldwide remains unknown due to a lack of awareness and diagnosis of the condition, the International Hyperhidrosis Society estimates that over 5% of the world’s population is affected by hyperhidrosis.

Who is at risk of hyperhidrosis?

According to research studies, the following groups have the highest risk of developing hyperhidrosis:¹  

• People aged between 20-60 years of age, with people younger than 25 years of age showing the highest incidence of hyperhidrosis 
• Although hyperhidrosis sweat affects all races and ethnicities, Japanese people appear to have the highest risk 
• People who have a family history of hyperhidrosis
• Menopausal women 
• People who take certain medications
• People with underlying medical conditions, such as diabetes, Parkinson’s disease, thyroid disorders, and cancer 

When should I see a doctor?

See a doctor immediately if profuse sweating:

• Disrupts any aspects of your life, whether social, emotional, physical, and/or psychological 
• Causes social withdrawal 
• Causes night sweats 
• Worsens overtime  

Seek immediate medical attention if profuse sweating causes chest pain, dizziness, and/or queasiness. 

Summary

Hyperhidrosis is a serious and common medical condition that causes profuse sweating due to overactive sweat glands (eccrine glands). The sweating is unrelated to heat or exercise and mainly affects the axillae, face, palms, and/or soles. Primary hyperhidrosis is mainly caused by genetic factors while  secondary hyperhidrosis can be caused by overuse of medications and underlying medical conditions. 

A diagnosis of hyperhidrosis is often confirmed by a blood or urine test or a sweat test. Current hyperhidrosis treatment and management options mainly include prescription-strength cloth wipes, aluminium-based antiperspirants, iontophoresis, and botox injections. Severe emotional and psychological distress and compensatory sweating are the main complications of hyperhidrosis. See a doctor immediately if your sweating worsens, you experience emotional distress, you begin to experience night sweats, or you experience chest pain, dizziness and queasiness during excessive sweating.