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Symptoms of Low Blood Sugar

Table of Contents


Topic 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:

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:

Symptoms of severe low blood sugar

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

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:

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:

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 for Symptoms of Low Blood Sugar

Current as of: July 28, 2021

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


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