Sweat is the body’s natural way to control its temperature. A person usually sweats due to physical exertion, raised body temperature, or exposure to heat. The sweat acts as a coolant, reducing the temperature inside the body. In other cases, a person may sweat in their armpits or on the palms of their hands because of emotional or mental stress.
When a person experiences excessive sweating, it is called hyperhydrosis or diaphoresis. In diaphoresis, the sweating cannot be explained by external heat or exercise. Instead, it is often the result of an underlying medical condition or someone’s medication.
Why Some People Sweat Excessively
Normally, your sweat glands produce perspiration that’s carried to the skin’s surface when the air temperature rises, you develop a fever, you’re exercising, or you’re feeling anxious, nervous, or under stress. When those factors are no longer an issue, the nerves that signal sweating are put on hold. For the 1% to 2% of the population who have hyperhidrosis, however, the sweat glands don’t shut off. They sweat even when the circumstances don’t call for it: when they’re in air conditioning, or while they’re sitting and watching television. Some people even tell their doctors that they sweat in a swimming pool.
The causes of hyperhidrosis depend on the type of sweating occurring. Most times, excessive sweating is harmless. In some cases, doctors don’t know why people sweat too much. In other cases, the causes of hyperhidrosis may be a medical condition that you don’t want to miss. If the sweating can be attributed to an underlying medical condition, it’s called secondary hyperhidrosis.
Health Conditions That May Cause Excessive Sweating
- Diabetes: For someone who has diabetes, profuse sweating can signal hypoglycemia or low blood sugar. In these situations, a person needs to bring their blood sugar levels back up. Hypoglycemia can cause severe complications and be life-threatening if not treated urgently.
- Hyperthyroidism: Hyperthyroidism is a condition in which there are too many thyroid hormones circulating through the body. The symptoms vary widely and are more pronounced in the later stages of the condition. Hyperthyroidism speeds up the body’s chemical processes, hence the possibility of excessive sweating.
- Cancer: The types of cancer that can sometimes cause sweating include Non-Hodgkin’s lymphoma and Hodgkin’s lymphoma, carcinoid tumours, leukaemia, mesothelioma, bone cancer and liver cancer. People with advanced cancer of any type sometimes experience excessive sweating.
- Glucose control disorders: Glucose control disorders include types1 and 2 diabetes, gestational diabetes and hypoglycaemia (abnormally low glucose levels). Excessive sweating is often a symptom of low glucose levels.
- Menopause: Many menopausal women report suffering from so-called hot flushes. 75% of women report hot flushes and sweating during menopause and the run-up to menopause. In some women it is so severe that a change of clothing is called for. Doctors suspect that hot flushes and sweating are caused by fluctuating or decreasing estrogen levels, which drop dramatically when periods finally stop.
- Psychiatric problems: Extreme stress and anxiety disorders can cause excessive sweating. Anxiety and stress can cause the body temperature to rise, which can lead to sweating. The embarrassment brought about by excessive sweating can lead to more anxiety, which can lead to further sweating. Some psychiatric drugs can also lead to excessive sweating. Withdrawal from many legal and illegal substances (including alcohol and opiates) can be accompanied by prolonged sweating.
- Pregnancy: Weight gain and fluctuations in hormones can cause sweating during pregnancy. Many women sweat more during pregnancy than at other times in their lives. Sweating during pregnancy can occur because of weight gain, hormone fluctuations, increased metabolism. Most pregnancy-related sweating is normal, but a woman should see a doctor if she experiences excess sweating combined with fever, chills, or vomiting. These symptoms could be signs of other conditions or an infection.
- Obesity: Carrying extra weight can make a person more prone to sweating. This can be due to increased exertion from carrying more weight or holding on to heat.
- Heart attack: A heart attack is a medical emergency. In addition to severe sweating, a person may experience chest pain, vomiting or nausea, faintness, pale face, shortness of breath, pain in the back, neck, jaw, or one or both arms.
- Anaphylaxis: Anaphylaxis is an extreme allergic reaction that can be life-threatening. In addition to sweating, a person may experience sudden decrease in blood pressure, itchy skin, narrowing airways, difficulty breathing, and loss of consciousness. A person should seek immediate medical help if experiencing anaphylaxis. Anyone who witnesses someone experiencing the symptoms of anaphylaxis should call emergency services straight away and use the person’s epinephrine injector (EpiPen) if available.
How Doctors Diagnose Excessive Sweating
Our doctors diagnose hyperhidrosis by doing a physical examination and listening to a patient’s history. We can also measure the level of sweating in two different ways:
- Starch Iodine Test: This is a test that turns the sweat brown and is used to detect excessive sweating (hyperhidrosis).
- Vapometer: This device measures transepidermal water loss and measures the amount of sweat that the hands, underarms, feet and scalp make. Measuring the amount of sweat gives your doctor an objective way to compare the amount of sweat before and after treatment.
How It is Treated
Excessive sweating can be challenging to treat and it may take a while to find a treatment right for you. Doctors usually recommend starting with the least invasive treatment first, such as powerful antiperspirants. Lifestyle changes may also help, including:
- wearing loose and light clothes,
- avoiding triggers, such as alcohol and spicy foods, that could make your sweating worse,
- wearing black or white clothes to help minimise the signs of sweating.
If these doesn’t help, you may be advised to try treatments such as iontophoresis (the affected area is treated with a weak electric current passed through water or a wet pad), botulinum toxin injections, and even surgery in a few cases.
Hyperhidrosis is usually a long-term condition, but some people experience an improvement with time and the treatments available can often keep the problem under control.
- Webmd.com: Excessive sweating medical condition
- Access Medicine: Disorders of the eccrine sweat glands and sweating.
- Mayo clinic: Excessive sweating