A condition in which the body's blood sugar level goes below the standard range.

Blood sugar, which also is called glucose, is the body's main source of energy. When blood sugar falls below a healthy level, it can cause a variety of problems. Hypoglycemia often is related to diabetes treatment. But other medicines and a variety of conditions — many of them rare — can cause low blood sugar in people who don't have diabetes.

Symptoms may include shakiness, sweating, headache, nausea, uneven heartbeat, fatigue, irritability, problems concentrating, dizziness, lightheadedness, and tingling or numbness of the lips, tongue or cheek. Confusion, loss of coordination, slurred speech or blurry vision can happen too. Severe cases may trigger a loss of consciousness or seizures.

Hypoglycemia needs treatment right away. Treatment involves quickly getting blood sugar back to within the standard range either with a high-sugar food or drink or with medicine. Long-term treatment requires finding and treating the cause of hypoglycemia.