General: It is normal for people to sweat when they are warm or experiencing emotional stress. Sweating helps maintain proper body temperature by keeping the body cool. When people are under stress, sweat glands contract, which pushes sweat to the skin surface.
There are many reasons why individuals may sweat too much or not enough. Below are some of the most common causes. However, some people may sweat more than others for no apparent reason.
Fevers: A common cause of increased sweating is fevers. A fever occurs when the body temperature is higher than normal. In general, the normal human body temperature should be around 98.6 degrees Fahrenheit. Fevers typically occur in response to infections. Patients often experience excessive sweating once the body temperature starts to return to normal. This is how the body cools itself down.
Foods and beverages: Certain foods and beverages may cause increased sweating. For instance, eating spicy foods or drinking hot beverages or drinks that contain caffeine or alcohol (such as coffee, tea, or beer) may increase sweating.
Heart attack: Severe sweating may also occur during a heart attack, when the heart becomes damaged due to a loss of blood supply. In addition to increased sweating, patients may also experience pain or pressure in the chest that radiates to the left shoulder, arm, or back. A heart attack is a medical emergency. Anyone who experiences these symptoms should seek immediate medical treatment.
Heredity: Excessive sweating, particularly of the palms of the hands and soles of the feet, can be inherited, or passed down from parents to their children. This is not considered a serious health problem, although it may be embarrassing for some people.
Low blood sugar (hypoglycemia): When individuals have low blood sugar levels, they may experience increased sweating in addition to weakness, hunger, shaking, and lightheadedness. This condition, called hypoglycemia, is common among diabetics.
Low testosterone levels (hypogonadism): Men who have hypogonadism, a condition that causes men to have low levels of the male hormone testosterone, may experience hot flashes. However, it is normal for older men (40-55 years of age) to have hot flashes when they experience a natural decline in testosterone levels.
Medications: Certain medications, including certain antipsychotic medications, morphine, high doses of the thyroid hormone thyroxine, and pain relievers (such as aspirin or acetaminophen), may increase sweating.
Menopause: A common symptom of menopause is hot flashes, which occur when a woman suddenly starts sweating because she feels extremely warm. Some women may also experience night sweats during sleep followed by chills. These symptoms occur because menopausal women have low estrogen levels. Symptoms usually last for less than one year after the last menstrual period.
Overactive thyroid (hyperthyroidism): Excessive sweating may also be caused by hyperthyroidism, which occurs when the thyroid gland produces too much of the hormone thyroxine. This hormone helps control growth and the rate at which the body uses energy (metabolism). Excessive sweating is a common symptom of hyperthyroidism along with sudden weight loss and irregular heartbeat.
Certain types of cancer: Some types of cancer, such as leukemia or lymphoma, may cause people to sweat more or less than normal.
Burns: Second-degree burns or third-degree burns, which affect several layers of skin, may destroy sweat glands. As a result, the affected area of skin will not perspire, even after the wounds are healed. This is typically a mild form of anhidrosis because in many cases, only a localized part of the body is affected.
Extreme dehydration: Extreme dehydration may lead to decreased sweating. This is because the body does not have enough fluid to produce sweat. Although dehydration can be easily reversed by drinking fluids, it is potentially life threatening. If left untreated, dehydration can cause heatstroke, kidney failure, brain swelling, seizures, shock, coma, and death. Signs of dehydration include dry skin, thirst, less frequent urination, light-headedness, and dark-colored urine.
Heatstroke: Heatstroke, a condition that occurs when the body temperature is extremely high, may also lead to decreased or absent sweating. Most cases of heatstroke are caused by overexertion, particularly in warm or hot climates. Other risk factors for heatstroke include dehydration, consumption of alcohol, heart disease, and certain medications. Heatstroke is a life-threatening condition because the body's internal organs start to shut down. Patients who experience decreased or absent sweating, rapid heartbeat, rapid and shallow breathing, increased blood pressure, irritability, confusion, unconsciousness, and fainting should be taken to the nearest hospital.
Horner's syndrome: A rare condition, called Horner's syndrome, may cause decreased or absent sweating. Horner's syndrome occurs when the sympathetic nerves of the face and eye become damaged. These nerves, which regulate sweating and circulation, may become damaged as a result of a tumor, stroke, or injury to the carotid artery. As a result, patients experience decreased sweating on the affected side of the face, as well as droopy eyelids and decreased pupil size.
Patients should visit their doctors if they suddenly start to sweat more or less than usual or experience night sweats for no apparent reason. Patients should also visit their doctors if they experience sweating that is accompanied by a fever and chills.
Since sweating problems are generally signs of an underlying condition, many different tests may be performed to determine the cause. For instance, blood tests may be performed to determine if the patient has low blood sugar levels, low testosterone levels (in men), low estrogen levels (in women), or high thyroxine levels. These conditions may lead to increased sweating.
In some cases, a doctor may be able to make a diagnosis after a detailed medical history and physical examination. For instance, a doctor may determine that medication is causing increased sweating if the patient is taking drugs that are known to increase sweating.
signs and symptoms
General: It is normal for sweat to occur in response to heat, exercise, anxiety, nervousness, or stress.
Excessive sweating: Individuals who experience excessive sweating may sweat even when they are not exercising or exposed to emotional stress. Some people may inherit a tendency to sweat heavily, particularly on the palms of the hands and soles of the feet. This is not a serious health problem, although it may be embarrassing for some people.
Some people may experience hot flashes. This occurs when a person suddenly feels extremely warm for no apparent reason and begins to sweat profusely.
Some people may experience night sweats during sleep. Patients may wake up covered in sweat in the middle of the night and experience chills.
Sweating may also occur in combination with other symptoms. For instance, if a person has an infection, he/she may have a fever, chills, and feel nauseous in addition to sweating. When people have low blood sugar levels, they may experience increased sweating in addition to weakness, hunger, shaking, and lightheadedness.
Decreased or absent sweating: People with decreased or absent sweating do not sweat enough in response to heat, exercise, or emotional stress. The severity of decreased sweating depends on the underlying cause.
Fungal infections: Individuals who sweat excessively have an increased risk of developing many types of fungal infections, including those that affect the nails, feet, and genitals. This is because fungi prefer warm, moist environments.
Patients who sweat excessively are prone to a fungal nail infection called onychomycosis. Patients may develop discolored, thick, brittle, or crumbly fingernails or toenails, which may be painful. The nails may become distorted in shape, flat, or dull.
Patients who sweat a lot are also prone to athlete's foot, a fungal infection of the foot that causes itching, stinging, and burning anywhere on the feet. Symptoms are usually most noticeable in between the toes. Patients may also develop itchy blisters, cracked or peeling skin, dry skin, or toenails that are thick, crumbly, discolored, or pulling away from the nail bed.
Jock itch, a fungal infection that affects the skin of the inner thighs, buttocks, and genitals, is also common among patients who sweat a lot. Symptoms typically include a red, itchy or burning rash that may cause the skin to become flaky.
Bacterial infections: Individuals who sweat excessively are prone to bacterial infections, especially between the toes or near hair follicles.
Warts: People who sweat a lot have an increased risk of developing warts, which are skin growths caused by the human papillomavirus (HPV).
Heat rash: Excessive sweating, especially in hot, humid weather, may lead to heat rash. The excessive sweat damages the cells on the skin's surface and blocks the sweat glands. As a result, the sweat is trapped under the skin causing tiny red bumps to form, usually on the upper back, chest, or arms. As the bumps burst and sweat is released, patients may feel a prickly or stinging sensation.
Heatstroke: Heatstroke may cause some cases of anhidrosis. However, it may also develop as a complication of anhidrosis that affects many parts of the body. If a patient has severe anhidrosis, the body is prone to becoming overheated. This is a serious life-threatening condition because the body's internal organs start to shut down in response to extreme temperatures. Patients who experience decreased or absent sweating, rapid heartbeat, rapid and shallow breathing, increased blood pressure, irritability, confusion, unconsciousness, and fainting, should be taken to the nearest hospital.
Social and emotional effects: Patients who sweat excessively may feel embarrassed, especially if the sweat is visible through the clothing or it causes an offensive odor. For instance, if the palms of the hands are excessively sweaty, the hands may feel clammy, and the person may feel uncomfortable shaking hands with others.