Diaphoresis · What Is It, Causes, Signs, and More

Diaphoresis, also known as generalized hyperhidrosis, refers to excessive sweating or perspiration that is not due to physical exertion or warm temperatures.

The cause of diaphoresis can be unknown, or idiopathic, or due to a known cause, called secondary diaphoresis. Seconday diaphoresis occurs as a result of an underlying medical condition, during menopause, during pregancy, or as a side effect of certain medications. Medical conditions that can cause diaphoresis include thyroid disorders, diabetes mellitus, and endocrine tumors. The thyroid is a gland in the neck responsible for producing hormones such as thyroxine. When the thyroid is overactive, as in the case of hyperthyroidism, increased thyroxine production results in an increase in the body’s metabolic rate, which can lead to diaphoresis. People with diabetes mellitus can have low blood sugar levels at times, which activates the body’s sympathetic system and can lead to excessive sweating. Additionally, endocrine tumors can form on the thyroid glands or in other glands that produce hormones such as the adrenal and pituitary glands. This can result in an excessive production of hormones, such as cortisol, which increases sweating. Menopause can cause episodes of excessive sweating, commonly known as “hot flashes.” This occurs as a result of hormonal changes, specifically decreases in estrogen, which lead to dysregulation of the hypothalamus (i.e., a gland in the brain that acts as the thermostat of the body). Pregnancy can similarly lead to diaphoresis due to hormonal changes, including decreased estrogen levels. 

The signs and symptoms of diaphoresis include excessive sweating without typical external triggers such as warm climate or exercise. In diaphoresis, sweating occurs on large, generalized areas of the body. The symptoms usually start in adulthood and can occur both during the day and at night. If an individual has diaphoresis associated with hyperthyroidism, they may also experience palpitations (i.e., heart pounding or racing), shaking hands, nervousness, and weight loss. Those with poorly controlled diabetes mellitus can experience diaphoresis accompanied by dizziness, anxiety, temporary loss of vision, and extreme fatigue as a result of hypoglycemia. 

Diagnosis of diaphoresis relies on an individual’s report of their symptoms. A clinician may be consulted when the amount of sweating is impairing their quality of life (e.g., sweating profusely through multiple changes of clothes, avoiding social situations due to diminished confidence as a result of diaphoresis). An individual should also seek immediate medical attention if they have experienced accompanying unexplained weight loss as that can point towards an underlying malignancy, including endocrine tumors. The clinician will often perform a thorough physical examination and ask focused questions to determine the underlying cause. 

The treatment for diaphoresis depends on the cause. If caused by hyperthyroidism, medications such as methimazole and propylthiouracil can be given. If the symptoms of hyperthyroidism are refractory to medication, radioactive iodine or radioactive thyroid ablation can be used to reduce the production of excess hormones. Additionally, management of diabetes mellitus relies on proper control of glucose levels in the body and can include lifestyle modifications, medications, or a combination of therapies. If an individual is going through menopause, they may consider hormone replacement therapy. Those with medication-induced diaphoresis may need the dose adjusted or try an alternative medication.