The Link Between Diabetes and Excessive Sweating

Diabetes is an endocrine disorder, which means that it impacts many different systems in our body. Because of this, it's harder to maintain a steady internal body temperature, a process called thermoregulation. Diabetes throws off the body's natural ability to balance body temperature.

High or low blood sugar levels can lead to hyperhidrosis (excessive sweating) or anhidrosis (lack of sweating). Hyperhidrosis is more commonly experienced in those with diabetes and may signal a need for tighter glucose management. Anhidrosis or reduced or absent sweating is less common but may be experienced in the feet or legs of people with diabetic neuropathy.

Research shows that up to 84% of people with diabetes experience sweating when they’re hypoglycemic, with the most common sweat area being behind the neck. Fortunately sweating in those with diabetes is often due to mildly low blood sugar episodes that usually go away shortly after you take in some sugar.

Types

There are three different types of sweating issues that may arise due to diabetes:

• Hyperhidrosis
• Gustatory sweating
• Night sweats

Hyperhidrosis

Adrenaline causes excessive sweating, or hyperhidrosis, as part of a counter‐regulatory hormonal response to the low glucose.

The body wants to stay within very narrow hormonal ranges to maintain homeostasis (the body's need to reach and maintain a certain state of equilibrium). Whenever this is thrown off, as is the case in diabetes, thermoregulation is disrupted and hyperhidrosis may occur.

Gustatory Sweating

Gustatory sweating is a common manifestation of diabetes mellitus that is not often appreciated.  The unusual phenomenon is characterized by excessive sweating of the face, scalp, and neck after ingestion of food and/or drink.

Gustatory sweating is seen in long-standing diabetes and is associated with nephropathy, peripheral neuropathy, and other conditions that disrupt our autonomic system. Profuse head and neck sweating after eating are usually all that is needed to make a clinical diagnosis.

Night Sweats

At night, the body uses energy from the carbohydrates you eat during the day to repair and restore itself. If you have not consumed enough carbohydrates, the body's thermoregulatory system may go awry.

The key to avoiding night sweats is to monitor your symptoms prior to going to bed. If caught early, your low blood sugars may be corrected quickly by consuming a simple carbohydrate like crackers or a piece of fruit. The amount you sweat is often directly proportional to your blood sugar levels, which means the greater length of time your blood sugar is low, the more you will sweat.

Causes

The most common cause of excessive sweating, especially at night, is hypoglycemia or low blood sugar. Adrenaline is produced in response to declining blood sugar levels, which results in the narrowing of blood vessels and the activation of sweat glands. 

Low blood sugar can happen for a number of reasons, including:

• Taking too much insulin
• Not consuming enough carbohydrates
• Skipping a meal or snack
• Excessive exercise (without adjusting your medication)
• Taking too much of an insulin-producing medication
• Drinking alcohol

Sweating is a common symptom in those with diabetes, but it rarely happens alone.

Symptoms of hypoglycemia can include:

• Feeling shaky
• Being nervous or anxious
• Clamminess
• Chills
• Irritability
• Confusion
• Racing heartbeat
• Lightheadedness or feeling as if you are going to faint
• Hunger
• Nausea
• Pale skin color (due to a lack of blood flow)
• Fatigue
• Blurred, double, or impaired vision
• Numbness or tingling in the lips, tongue, or cheeks
• Headache
• Coordination problems, clumsiness
• Nightmares or crying out during sleep
• Seizures

Diagnosis

Excessive sweating is a clinical diagnosis based on your symptoms and sometimes a few diagnostic tests. A healthcare professional may check your blood sugar and treatment regimen, as diabetic hypoglycemia is often the culprit of your excessive sweating.

Diabetic hypoglycemia occurs when your blood sugar level is below 70 ml/dL. Oftentimes, the presenting symptom is night sweats with people often recounting nightmares and waking up in damp sheets or nightclothes due to perspiration.

If you have access to a dermatologist, you may want to consult one to help pinpoint your problem. During your consultation, a healthcare provider may ask you the following questions:

• Do any of your blood relatives have excessive sweating?
• Do you sweat a lot while sleeping?
• When did you first notice the excessive sweating?
• Do you avoid certain activities or social situations because of your sweating?
• How often do you sweat excessively?
• Does anything seem to trigger your sweating?

Treatment

Treatment of excessive sweating depends on the severity, cause, and local vs. widespread symptomatology.

Local treatments include:

• Aluminum chloride 15% to 25% or antiperspirants
• Tap water iontophoresis for palmar/plantar sweating
• Glycopyrrolate for gustatory sweating
• Botulinum toxin (Botox) injections

Oftentimes, diabetes-induced sweating results in generalized sweating around the body. Systemic treatments to control sweating include:

• Anticholinergic drugs (e.g., methanthelinium bromide)
• Tricyclic antidepressants (e.g., amitriptyline)
• Beta-blockers
• Calcium channel blockers (e.g., diltiazem)

Surgery may be considered for more severe symptoms. These include:

• Endoscopic thoracic sympathectomy
• Axillary curettage, liposuction for axillary hyperhidrosis

Coping

If you have excessive sweating caused by diabetes, it may impact your relationships, confidence, and ability to carry out daily activities. Fortunately, there are ways to manage your symptoms and ease sweating-induced anxiety.

Carrying antiperspirant and a change of clothes and taking an extra shower per day may be small—albeit sometimes difficult—changes that you can make to help cope with your symptoms. You may also want to consider keeping a sweat journal that tracks common triggers of your perspiration. Common triggers include heat, feeling anxious, and certain foods, especially those that contain:

• Monosodium glutamate (MSG)
• Caffeine (chocolate, coffee, tea)
• Spices such as curry or cumin
• Alcohol

A Word From Verywell

Excessive sweating in diabetes is a common symptom that is often overlooked. If you are sweating during the day, after eating, or at night, you may want to take a closer look at your blood sugar levels and make changes to your treatment regimen. Fortunately, the resolution of your hypoglycemia leads to a vast amelioration of your sweating.

Getting your sweating under control may not be easy at first, but addressing the issue head-on will help to preserve your confidence, increase your social interactions, and help you to live a worry-free life.