Is sweating a sign of low blood sugar

Do you find yourself waking at night drenched in sweat and feeling hot and clammy – even when the room is cold? You’re not alone. Night sweats are a common symptom of nocturnal hypoglycemia – the night-time low blood sugar episodes experienced by some diabetics.

What is nocturnal hypoglycaemia?

Not heard diabetic night sweats referred to as nocturnal hypoglycaemia before? Nocturnal hypoglycaemia is when a hypoglycemic episode happens as you sleep. It is more common in people who control their diabetes with insulin and often you will only realise you’ve experienced a night time hypo on waking up. You may only discover night time hypos when you wake with some or all of the following nocturnal hypoglycemia symptoms:

• Headache
• Clammy neck
• Damp from excessive sweating
• Feeling fatigued

What causes night sweats in diabetics?

The main cause of night sweats in diabetics is low blood sugar at night (hypogylcemia).

When blood sugar levels drop, this can cause a number of sleep-disturbing symptoms, including headaches and excessive sweating. While night sweats can occur across the whole body, in people experiencing nocturnal hypoglycemia, the neck often becomes noticeably sweaty, making this a key sign to look out for.

So what causes diabetes and night sweats? Essentially, this is anything that could cause glucose levels to drop overnight. Some of the most common causes of nocturnal diabetes include:

• Insulin use: Hypoglycemia is more common in diabetics who use insulin to manage their condition.
• Exercise: Being more active means you’ll have used more glucose during the day. In particular, exercising in the hours before bed increases the chances of low blood sugar at night.
• Alcohol: Drinking alcohol in the hours before bed can decrease your liver’s ability to produce glucose overnight.

Dealing with low blood sugar and night sweats

For the most part, dealing with diabetic night sweats and nocturnal hypoglycaemia means making sure that you manage your condition to reduce the risk of experiencing low blood sugar levels at night.

The following tips can help:

• Test your glucose levels before bed: If levels are already on the low side, you can take preventative action before going to sleep.
• Watch what you eat in the evening:
  • Avoid wine, beer or other alcoholic drinks in the hours before bed
  • Increase snacking if you’ve been more physically active during the day
  • Avoid hot and spicy foods as these can cause night sweats even in those who don’t have diabetes
• Reschedule your exercise routine: If you usually workout in the evening, try moving this to earlier in the day.
• Speak with your GP: They may be able to advise on changes to your medication to help ease nocturnal hypoglycaemia symptoms. It’s also important to remember that while night sweats are quite common for diabetics, they can also be a sign of other underlying conditions. Discuss your night sweats with your GP to eliminate any other possible causes.

How to get relief from diabetic night sweats

Taking steps to prevent the nocturnal hypoglycemia that can cause diabetic night sweats is the first and most important thing. But there are also a number of steps you can take to alleviate the symptoms of diabetic night sweats and get a better night’s sleep.

• Keep your bedroom cool: Turn heating off or down to an absolute minimum in the hours before bed. You can also try leaving a window open or keeping a fan running to improve ventilation.
• Choose natural nightwear: Sleep in natural fibers such as cotton, wool or silk. These materials are more breathable and more effective at absorbing moisture than synthetic alternatives such as polyester. So, you can stay cool and avoid that clammy feeling.
• Sleep in natural bedding: As with nightwear, bedding made from natural fibers is more effective at regulating temperature and absorbing moisture. For maximum benefit try wool bedding as this natural fiber is more absorbent than feather/down alternatives. Partner a wool duvet, pillows and protector with cotton sheets and covers for best performance.

Want to know more about your health and sleep? Learn about the other reasons for night sweats, from hot flushes to medication and more. Visit our Sleep Health & Advice Hub today.

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Overview

Symptoms of mild low blood sugar

You may have these symptoms when your blood sugar has dropped below 70 milligrams per deciliter (mg/dL). When you have had diabetes for many years, you may not always develop symptoms of mild low blood sugar.

Some young children with diabetes cannot recognize symptoms of low blood sugar. Others can, but not every time. To be safe, the parents need to do a home blood sugar test whenever they suspect low blood sugar in a child.

Symptoms may include:

• Sweating (almost always present). Check for sweating on the back of your neck at your hairline.
• Nervousness, shakiness, and weakness.
• Extreme hunger and slight nausea.
• Dizziness and headache.
• Blurred vision.
• A fast heartbeat and feeling anxious.

These symptoms may go away shortly after you eat food that contains sugar.

Symptoms of moderate low blood sugar

If your blood sugar continues to drop (below 40 mg/dL), your behavior may change. Symptoms may include:

• Inability to concentrate.
• Confusion and irritability.
• Slurred speech.
• Unsteadiness when standing or walking.
• Muscle twitching.
• Personality changes, such as anger or crying.

Symptoms of severe low blood sugar

Symptoms of severe low blood sugar (usually below 20 mg/dL) include:

• Seizure.
• Loss of consciousness (coma).
• Stroke.
• Death.

Signs of low blood sugar at night

If your blood sugar drops while you are sleeping, your partner or other family members may notice that you are sweating and behaving differently. Signs of low blood sugar at night (nocturnal hypoglycemia) include:

• Restlessness.
• Making unusual noises.
• Attempting to get out of bed or accidentally rolling out of bed.
• Sleepwalking.
• Nightmares.
• Sweating.

You may wake up with a headache in the morning if your blood sugar was low during the night.

Signs of hypoglycemic unawareness

Some people have no symptoms of low blood sugar. The only symptom you may have is confusion. Or you may become unconscious before anyone realizes you have low blood sugar.

You may have hypoglycemic unawareness if you:

• Cannot tell by your symptoms that your blood sugar is low.
• Have low blood sugar several times a week.
• Have type 1 diabetes, or have had type 2 diabetes for a long time.

If you have hypoglycemic unawareness, test your blood sugar often, especially before activities like driving a car. Keep quick-sugar foods with you. If you take insulin, carry a glucagon emergency kit. You can also give friends and family instructions to treat low blood sugar.

Credits

Current as of: April 13, 2022

Author: Healthwise Staff
Medical Review:
E. Gregory Thompson MD - Internal Medicine
Adam Husney MD - Family Medicine
Kathleen Romito MD - Family Medicine
Rhonda O'Brien MS, RD, CDE - Certified Diabetes Educator

The Health Encyclopedia contains general health information. Not all treatments or services described are covered benefits for Kaiser Permanente members or offered as services by Kaiser Permanente. For a list of covered benefits, please refer to your Evidence of Coverage or Summary Plan Description. For recommended treatments, please consult with your health care provider.

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