How does diabetes cause abnormal sweating?
Diabetes can make it difficult for a person's body to maintain a steady temperature and to produce the right amount of sweat to keep the body cool.
Sweating complications can be a sign that a person needs to review their diabetes management, including the effective management of blood sugar levels.
Diabetes and sweating
Sweating helps cool the body, but diabetes can disrupt a person's ability to sweat.
Sweating mainly happens for two reasons:
- To regulate body temperature, for example, in hot weather and during physical activity
- In response to emotional stress
Certain medical conditions, such as diabetes, can disrupt normal sweating, so that a person sweats too much or too little.
This can lead to problems during hot weather, but the inability to regulate body temperature can also put a person at risk in cold temperatures.
Excessive sweating without a clear reason, on a cool day, or during times of minimal activity may be a sign that a person should see a doctor.
Sweating may affect:
- the underarms
- the face and possibly chest and neck
- the hands and feet
The most common reasons for unusual sweating in people with diabetes are:
- low blood sugar levels
- diabetes-related nervous system damage
Very low blood sugars — usually below 70 milligrams per deciliter (mg/dl) — can result in a fight-or-flight response, triggering the release of hormones that increase sweating.
When blood sugar levels are too high for too long, a loss of nerve function can occur, known as diabetic neuropathy.
Damage to the nerves that control the sweat glands can result in them sending the wrong message to sweat glands, or none at all. This can result in too much or too little sweating.
Neuropathies and sweating
When the body gets too warm, the nervous system signals to the sweat glands to release sweat to cool it down. Sudomotor function describes the part of the nervous system that controls sweating.
Diabetes can result in nerve damage, so that, for some people, the nerves that control sweat glands are always "switched on."
This can result in excessive sweating, known as hyperhidrosis.
People with diabetes-related hyperhidrosis may experience excessive sweating or sweat more than most people in the following circumstances:
- during times of little activity, including sleeping and minor chores
- in a cool environment
- when trying to get warm by wearing extra clothing or seeking a heat source
- during times of stress
If a person uses a dose of insulin or other diabetes medications that is higher than they need, blood sugar levels can fall.
This may happen if the person:
- takes too much insulin or another drug
- exercises intensely or more than they expected
- eats less than usual or misses a meal
There are two reasons why hypoglycemia can lead to sweating.
Low blood sugars can affect activity in the autonomic nervous system (ANS), which is responsible for reactions that people cannot control, such as sweating and digestion. The cholinergic system is a part of the ANS, and it regulates the production of sweat and other secretions. Activation of this system can lead to sweating.
The release of the hormone epinephrine, or adrenaline, is another possible trigger. Adrenaline is a hormone that the body releases at times of stress, sometimes called the "fight-or-flight hormone." One effect of a sudden increase in adrenaline is sweating.
Hypoglycemia needs treatment, as it can be life-threatening.
- Short-term treatment for mild symptoms includes taking a glucose tablet to raise blood sugar levels quickly. A person who has frequent or persistent hypoglycemia should see a doctor.
- In severe cases, a person can experience confusion, seizures, or a loss of consciousness. Someone should call 9-1-1 as this is a medical emergency. It can be life-threatening.
Treatment and prevention
A doctor may prescribe the following to reduce or control sweating with diabetes:
Clinical strength or prescription antiperspirants: Products that contain high doses of aluminum chloride can prevent sweating by blocking sweat pores. However, skin irritation is a common side effect.
Nerve-blocking medications: A doctor may prescribe oral medications, known as anticholingerics. These block the chemical messenger called acetycholine that can affect certain functions in the body, including the release of sweat. Dry mouth, bladder problems, dehydration, and blurred vision are common side effects.
Botox (Botulinum toxin) injections: Botox can block sweat-producing nerve signals. Side effects include short-term muscle weakness near the injection site and target area.
Other options may include:
- some antidepressant medications
- surgery and electrical current therapy
Home remedies for sweating
Good hygiene and cotton clothing that allows air movement can reduce sweating. .
Home therapy options for managing symptoms include:
- maintaining regular body hygiene
- wearing natural fabrics rather than synthetic, such as cotton shirts, socks, and underwear
- changing items of clothing daily or more often when they become sweaty
- not wearing the same pair of shoes day after day
- wearing open shoes when possible and making sure feet get air throughout the day
- choosing natural fabrics for clothing and shoes, such as cotton and leather that allow air movement
- choosing sports clothes that are made of "wicking" materials, as these move moisture away from the body
Deodorants and other products are available for purchase online.
Facial or gustatory sweating
Facial, or gustatory, sweating occurs on the face, scalp, neck, and, occasionally, the chest.
Gustatory relates to the sense of taste.
According to research published in Diabetes Care, it is a rare form of sweating that happens because of nerve damage.
For many people, this is a familiar reaction to eating hot or spicy foods, but people with diabetic neuropathy may experience facial sweating to a greater degree.
The person may find that they sweat and become red in the face while eating, regardless of the temperature or spiciness of foods.
Some people will start to sweat when they think about eating or food.
Sweating may occur on the:
- forehead and temples
Treatment options include:
- appropriate blood sugar management
- topical antiperspirants
- Botox injections
- anticholinergic drugs to apply topically
Damage to the salivary glands, due to surgery or other reason, can also result in gustatory sweating.
Over time, the combination of facial sweating and flushing can injure these glands, causing a condition known as Frey's Syndrome.
Learn more here about Frey's syndrome and how to prevent sweating after eating.
Inability to sweat
The body of a person with anhidrosis does not produce enough sweat.
Anhidrosis refers to an inability to produce enough sweat. This means that the body will find it hard to keep cool in a hot environment.
As with excessive sweating, this can result from damage to the nerves that control the sweat glands.
In anhidrosis, the sweat glands do not receive the signal to sweat, even when sweating would usually occur.
People with type 1 diabetes tend to sweat more than usual in the upper body and less than usual in the lower body, which can lead to overall anhidrosis, according to research.
They may also have lower blood volume and less effective blood flow.
These cardiovascular problems can also contribute to overheating. As the blood flows under the skin, this helps a person to keep cool. If it does not flow effectively, overheating can result.
Symptoms of anhidrosis and overheating can include:
- difficulty staying warm or cool enough
- little or no perspiration
- trouble cooling down, even after minor tasks
- becoming overheated during minor physical tasks or a warm environment
- facial flushing
- muscle cramp and weakness
- a rapid heartbeat
If symptoms are severe or affect large areas of the body, the person should see a doctor.
Treatment options mainly focus on cooling the body, for example, by:
- drinking cool fluids
- taking a cold shower
- adjusting the room temperature, if possible
- avoiding intense physical exercise in a hot environment
If a person's body cannot maintain a consistent or healthy temperature, serious health complications can arise, such as heat exhaustion and heat stroke.
Studies show that people with diabetes are more likely to experience discomfort and medical problems leading to hospitalization during hot weather than those without the condition. The inability to keep the body cool can be life-threatening.
For this reason, it is important to seek medical help if a person finds they are unable to keep cool or to cool down.
Other causes of high or low sweating
Diabetes is not the only reason for problems with sweating.
Anyone who feels they are sweating more or less than usual should see a doctor, as it can be a sign of a health condition.
Other common conditions that can trigger excessive sweating include:
- an overactive thyroid gland
- some forms of cancer
- some heart conditions
- menopause and hot flashes
- the use of certain medications
- fever during an infection
Other causes of low sweating may include:
- conditions that have affected the sweat glands from birth
- skin damage
- other causes of nerve damage, such as alcohol abuse disorder
- certain pain and psychosis medications
- many metabolic conditions
Sweating is an important function that enables the body to maintain a steady temperature. Excessive sweating can be embarrassing, but reduced sweating can lead to overheating, which can be dangerous.
Managing blood sugar levels and following the treatment plan is one way to reduce the risk of sweating problems.
Anyone who is concerned about sweating rates or the inability to maintain a comfortable body temperature should seek medical help.
What over-the counter deodorant and other products would you recommend to reduce sweating?
Excessive sweating can cause discomfort and embarrassment. There are a few over-the-counter products that can help. Aluminum-based antiperspirants can temporarily block pores which prevent sweat from reaching the skin surface, and an astringent containing tannic acid can also help. Clothing, socks, and shoes made of natural materials such as cotton, wool, and leather allow the skin to breathe which can also help reduce sweating.Elaine K. Luo, MD Answers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.