Low Blood Sugar is Hypoglycemia and not hyperglicemia
The symptoms of hypoglycemia may vary from episode to episode because low blood sugar can be mild, moderate, or severe. Increasingly severe symptoms appear as the blood sugar level falls.
In healthy people, fasting blood sugar levels are usually between 70 and 99 mg/dL.
Symptoms of mild low blood sugar usually occur when blood sugar falls below 70 mg/dL and may include:
Feeling nervous or jittery.
Cold, clammy, wet skin and/or excessive sweating not caused by exercise.
A rapid heartbeat (tachycardia).
Numbness or tingling of the fingertips or lips.
If blood sugar continues to fall, the nervous system will be affected. Symptoms usually occur when the blood sugar falls below 55 mg/dL and may include:
Mood changes, such as irritability, anxiety, restlessness, or anger.
Confusion, difficulty in thinking, or inability to concentrate.
Blurred vision, dizziness, or headache.
Weakness, lack of energy.
Difficulty walking or talking, such as staggering or slurred speech.
Fatigue, lethargy, or drowsiness.
The symptoms of severe low blood sugar develop when blood sugar falls below 35 mg/dL to 40 mg/dL and may include:
Seizures or convulsions.
Loss of consciousness, coma.
Low body temperature (hypothermia).
Prolonged severe hypoglycemia can cause irreversible brain damage and heart problems, especially in people who already have coronary artery disease. If emergency medical treatment is not provided, severe hypoglycemia can be fatal.
Some medicines may mask symptoms of low blood sugar, including beta-blockers, which are often used to treat heart conditions and high blood pressure.
What to think about
Different people may have symptoms of mild, moderate, or severe hypoglycemia at varying blood sugar levels. Although the blood sugar levels listed above are typical, they may not apply to everyone. If your blood sugar drops suddenly, you may have symptoms even if your level is in the normal range.
A number of medical conditions can cause symptoms similar to those of hypoglycemia. Your doctor will use blood tests and other measures to make sure another condition isn't causing your symptoms.
If you have diabetes, it is very important to check your blood sugar levels, because many diabetes treatments can cause low sugar levels.