Normal blood sugar levels range between 70 to 110 mg/dL, says MayoClinic.com. Although diabetics have high blood sugar, called hyperglycemia, side effects of their treatment may also cause hypoglycemia, or low blood sugar. A person with low blood sugar--below 70 mg/dL--may experience cold sweats, blurred vision, headache, irritability, fatigue, confusion, rapid pulse or convulsions, notes MedlinePlus from the National Institutes of Health. Hypoglycemia may occur for a variety of reasons but is not common among non-diabetics.
Medications
Hypoglycemia commonly occurs when a diabetic taking insulin or oral diabetic medications reduces his food intake or exercises more than usual, causing a drop in blood sugar, says the Merck Manual Home Edition. The risk of hypoglycemia in diabetics increases with age, kidney dysfunction and the duration of the condition. Some non-diabetic medications, including pentamidine for AIDS-related pneumonia and quinine for muscle cramps related to malaria, occasionally cause hypoglycemia as well.
Disease
Otherwise healthy people who fast for several days rarely experience hypoglycemic episodes, but long-term starvation related to eating disorders can cause hypoglycemia by depleting the body's stores of substances needed for glucose production, notes MayoClinic.com. Drinking excessive amounts of alcohol without eating inhibits the release of sugar from the liver, causing fasting hypoglycemia, says the Merck Manual Home Edition. Other liver conditions, including viral hepatitis, cirrhosis and cancer, may prevent the liver from storing enough sugar, causing hypoglycemia. Abnormalities of the enzymes that control blood sugar in infants and children; autoimmune disorders; kidney or heart failure; shock; and disorders of the pituitary and adrenal glands may also cause hypoglycemia, especially in diabetics.
Carbohydrate Reaction
Rarely, eating a high-carbohydrate meal may cause a normally healthy person to produce excess insulin, causing a hypoglycemic reaction, says the Merck Manual Home Edition. More commonly, patients who have undergone gastric bypass surgery may absorb refined sugars rapidly, causing excess insulin production, according to MayoClinic.com. This condition is known as reactive or postprandial hypoglycemia. Foods containing fructose, galactose or the amino acid leucine may produce hypoglycemia in individuals unable to digest those substances.
