Low blood sugar is also known as hypoglycemia. Hypoglycemia is a condition that causes an abnormally low level of blood sugar, or blood glucose. This is the body's main source of energy. People with diabetes get hypoglycemia when their bodies do not have enough sugar to use as energy. There are a number of things that can cause people to develop hypoglycemia. Some people may develop it as a result of their diet, exercise regimen, or as a result of being on certain medications. The symptoms of hypoglycemia usually begin when people’s blood sugar drops to 70 milligrams per deciliter or lower.

You are at risk of having a low blood sugar reaction if you:

Skip or delay a meal or snack

Take too much insulin or eat too few carbohydrates

Exercise

Drink alcohol, especially without eating carbohydrates

Check your blood sugar if you have any of these symptoms:

Weakness and/or fatigue

Headache

Sweating

Anxiety

Dizziness

Shaking

Increased heartbeat

If your blood sugar is less than 70 milligrams per deciliter (mg/dl):

Eat 15 to 30 grams of carbohydrate

Wait 15 minutes and then recheck your blood sugar

If your blood sugar is still less than 100 mg/dl, take another 15 grams of carbohydrate and retest your blood sugar in another 15 minutes. Repeat if necessary.