There are two types main types of hyperhidrosis, primary and secondary, of the two only 7% of the people suffering from hyperhidrosis have the secondary type. About 3% of the population has hyperhidrosis, so this is a relatively small population. Secondary generalized hyperhidrosis is a condition in which a person has excessive sweating due to an underlying issue. It is important to understand the basics of diaphoresis when discussing secondary hyperhidrosis. Diaphoresis is the term doctors use to describe unexplained excessive sweating and is often used in conjunction with a diagnosis of secondary hyperhidrosis, they can be used interchangeably to describe the condition. While the hyperhidrosis is not bad for a person's health by itself, the underlying causes can be.
Secondary hyperhidrosis is usually categorized by generalized sweating that occurs all over the body and is often worse at night. The onset of secondary hyperhidrosis usually occurs after the age of 25 and it has a specific cause. These causes can be broken down into three main groups: drug induced, physiologic or pathologic. The most common cause of secondary hyperhidrosis are medicines and the side effects they cause. However, there are a variety of physiologic states and diseases that can cause secondary hyperhidrosis so it is important that patients with this type of hyperhidrosis manage it with a doctor.
Physiologic States that Cause Hyperhidrosis
When discussing a physiologic cause of excessive sweating this describes the condition or state of the body or bodily functions that naturally occur and cause the symptoms of hyperhidrosis. This means the underlying cause of hyperhidrosis is not a disease but it is caused by a natural change in the body that results in unwanted excessive sweating. One of the best examples of this is pregnancy - it is a natural state of change in the body that causes some people to produce too much sweat.
Women are often subjected to secondary hyperhidrosis resulting from normal hormonal changes they experience over a lifetime. The two main culprits are pregnancy and menopause. During pregnancy several factors can cause a woman to sweat more than normal including increased blood volume, hormonal changes and extra weight. This all places more stress on the body and causes pregnant women to feel hot which induces sweating. This is a normal occurrence and should not lead to concern. Menopause begins at a median age of 51 and up to 80% of women experience sweating and flushing by the time the process has ended. Many women going through menopause experience hot flashes which cause sudden, intense sweats and night sweating as a result of changing hormone levels. There are blood tests to check oestradiol and gonadotropins, types of hormones, to ensure a woman is in menopause. It is recommended to do this to definitively determine that a woman is in menopause and make sure her hyperhidrosis is not being caused by another unrecognized condition. These types of hormonal changes eventually will resolve on their own but can be managed with medication if needed, especially in the case of a menopausal woman.
Other physiological states that can induce hyperhidrosis are obesity, excessive heat and fever. While obesity is not an optimal state for body function, it is a naturally occurring phenomenon. Excess weight can cause hormonal imbalances that impact thermoregulation and can cause a person to overheat more easily leading to excessive sweating. There is a reason why people sweat when they are sick with an infection or virus, this is known as fever. Fever is included in this section because it is a natural state the body induces for various reasons, most commonly to fight infection. It is important to note that a fever itself can be a cause of hyperhidrosis and not just the issue causing the fever. It causes excessive sweating as the body heats its core temperature and this initiates activates the sweat glands.
Diseases that Cause Secondary Hyperhidrosis
There are many diseases and pathologic conditions that have the potential to cause secondary hyperhidrosis. Included is a list of the most common diseases that can cause excessive sweating, broken down by which body system they affect:
These are diseases and conditions that impact hormones and structures that control and secrete them. Here are the most common endocrine conditions that can cause hyperhidrosis:
- Hyperthyroidism: This is over-activation of the thyroid gland and can be a common cause of sweating.
- Diabetes: This is a very common cause of disease-related hyperhidrosis. It is a condition in which patients bodie’s cannot appropriately deal with insulin.
- carcinoid syndrome: A syndrome caused by certain kinds of tumors.
- Hyperpituitarism: Over production of hormones by the pituitary gland.
- Pheochromocytoma: Tumor of the adrenal gland.
- Acromegaly: The body produces too much growth hormone, this can result in gigantism.
Of these conditions diabetes mellitus and hyperthyroidism are the most common.
Many infections have the potential to cause hyperhidrosis as a symptom, including:
- Acute bacterial or viral infections: These can include common illnesses that regularly circulate the population or more serious infections.
- chronic infections like:
- Tuberculosis: A rare but serious bacterial infection of the lungs.
- Malaria: A parasitic infection spread by mosquito.
- Brucellosis: A bacterial infection often caused by exposure to animals or animal waste products.
A large variety of neurological issues, those that deal with the brain and spinal cord, can cause hyperhidrosis. Here is a look at the most common:
- Stroke: Caused by the brain being unable to obtain blood flow. Can be due to a brain hemorrhage or a blocked blood vessel. These a common, serious and require immediate medical attention.
- spinal cord injuries: The body can no longer regulate the nerve signals going to the brain and this can impact thermoregulation and cause sweating.
- gustatory sweating after parotidectomy
- Parkinson's disease: Degenerative condition of the brain that eventually leads to death.
- Encephalitis: Swelling of the brain.
Heart failure, due to any reason, can cause secondary hyperhidrosis as a symptom. Some reasons for heart failure can include but are not limited to congestive heart failure, a heart defect, endocarditis (infection of the heart) and many others.
There are several types of cancer that can cause hyperhidrosis to result. Lymphoma, in particular is known to do this. Depending on tumor location and individual reactions patients with other types of cancer may also experience excessive sweating.
There are several other conditions that can cause secondary hyperhidrosis like gout, arsenic intoxication, alcoholism and congenital conditions that are fairly common. This is not a comprehensive list of conditions that can cause excessive sweating.
Due to the possible dangerous and debilitating conditions that may contribute to secondary hyperhidrosis, it is always important for a patient to manage the condition with a doctor. There are many natural and healthy reasons for why humans sweat but if excessive sweating has a sudden and intense onset it may be related to one of the conditions discussed above. Conversely, if you notice that you're body doesn't seem to sweat at all this can also be a worrisome sign. Any time you feel like your body is overproducing or underproducing sweat it is a good idea to speak to your doctor.
- Pariser, D. M. (2014). Hyperhidrosis (4th ed., Vol. 32). Philadelphia, PA: Elsevier.
- Physiologic. 2018. In Merriam-Webster.com. Retrieved August 16, 2018, from http://www.meririam-webster.com/dictionary/physiologic
- Paisly, A. N., & Buckler, H. M. (2010). Investigating secondary hyperhidrosis. BMJ : British Medical Journal (Online), 341. doi:10.1136/bmj.c4475
- Benson, R. A., Holt, P. J., & Loftus, I. M. (2013). Diagnosis and management of hyperhidrosis. BMJ : British Medical Journal (Online), 347. doi:10.1136/bmj.f6800