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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.
At some time, most people with diabetes experience the sweating and shakiness that occurs when blood glucose levels fall below 70 mg/dl — a condition known as hypoglycemia. The average person with type 1 diabetes may experience symptoms of low blood glucose up to two times a week. However,
not all are aware that these symptoms can rapidly progress to seizures, coma and even death if hypoglycemia is severe. Though hypoglycemia can be common and occur repeatedly in some people with diabetes, symptoms of low blood glucose should always be taken seriously. People with diabetes and their families, friends or coworkers should be prepared to act quickly and responsibly at the earliest signs of low blood glucose. Surprisingly, the most dangerous episodes of hypoglycemia occur with little or no warning. When low blood glucose occurs on a regular basis, the body can become used to the warning signs and the person may stop noticing symptoms. This is a particularly
dangerous condition known as hypoglycemic unawareness. People with this condition might not realize they have low blood glucose until it's dangerously low — seizures and coma are sometimes the first indication of a problem. The good news is that this condition can often be reversed — allowing people to once again notice the signs of low blood glucose — if hypoglycemia is avoided for a few weeks through careful monitoring of blood glucose. All
people with diabetes: Friends, relatives, coworkers and caregivers should be trained to recognize the signs of low blood glucose and know what to do — including how to inject glucagon in case of an emergency — as well as what not to do.The dangers of low blood glucose
Early signs of hypoglycemia:
Late signs of hypoglycemia:
What causes low blood glucose?
No symptoms? Be alarmed
How can I prevent low blood glucose?
Make an emergency plan