Hypoglycemia is the condition that occurs when blood sugar, or glucose, levels drop below normal.
Blood sugar levels drop when people don't eat for a long time, or when they have complications of diabetes and other diseases. The blood sugar level is affected by the hormones insulin and glucagon. An imbalance of these hormones can cause blood sugar levels to fall too low. When the blood sugar falls too low, hypoglycemia develops.
When blood sugar drops and hypoglycemia develops, most people will begin feeling weak, drowsy, excessively hungry, and dizzy. A person may feel confused or irritable. The person may appear pale, may tremble, or feel cold and clammy. A rapid heartbeat may also be felt. In severe cases, usually associated with diabetes, a person can lose consciousness and lapse into a coma.
Hypoglycemia usually occurs in people with pre-diabetes or diabetes.
When people have type 1 diabetes, the pancreas does not make enough insulin or the insulin made is not effective. When people have type 2 diabetes, they are resistant to insulin, usually because of obesity. In either case, blood sugar rises and builds up in the blood.
People with diabetes take insulin or oral medications to keep their blood sugar down. If a person with diabetes takes too much medication, misses meals, or doesn't eat enough food, the person can become hypoglycemic.
On occasion, hypoglycemia can occur in people who do not have diabetes. Hypoglycemia can also occur in early pregnancy. People can also become hypoglycemic if they fast for a long time or exercise for an extended period.
People taking certain medications, such as beta-blockers or aspirin, may become hypoglycemic more easily. Sometimes people who are alcoholics or binge drinkers can become hypoglycemic.
The single greatest short-term risk is injury to oneself or others while driving a car or operating heavy equipment, caused by the confusion or irritability that accompanies hypoglycemia.
People with diabetes prevent hypoglycemia by frequently monitoring blood glucose levels and recognizing early symptoms of hypoglycemia. People who have diabetes can prevent hypoglycemia by keeping their blood sugar levels within their recommended range. They are trained to recognize when their blood sugar levels are dropping. They can quickly eat or drink something with sugar or take glucose tablets to prevent hypoglycemia from developing. Other people who have hypoglycemia can learn to eat and exercise in a way that does not cause their blood sugar to drop too low.
Hypoglycemia is diagnosed when a person complains of symptoms. Blood glucose levels are then measured. If the blood glucose levels are 45 mg/dL or less in women or 55 mg/dL or less in men, hypoglycemia is present. Finally, if the symptoms go away upon eating sugar or drinking a beverage with sugar, then the person probably has hypoglycemia.
Repeated episodes of hypoglycemia are now thought to cause mild forms of brain damage that may be irreversible. Rarely, severe hypoglycemia can cause a coma or death.
There are no risks to others. This condition is not contagious.
The treatment for hypoglycemia is control of blood sugar levels. People with diabetes learn the early warning symptoms and quickly eat or drink a sugary substance. The same treatment works for people without diabetes who have hypoglycemia. Usually all people with hypoglycemia are advised to follow a healthy eating plan with a variety of foods eaten at regular intervals throughout the day.
Too much sugar can cause the level of blood sugar to go too high. This is rarely a problem, except in people with severe diabetes.
People begin to feel better very quickly after they bring up their blood sugar to normal ranges. The uncomfortable physical symptoms soon disappear after eating or drinking something with sugar.
People who become hypoglycemic easily, whether they have diabetes or not, learn to monitor their symptoms. The best way to avoid the uncomfortable, and sometimes dangerous, symptoms of hypoglycemia is to prevent the problem in the first place. People with diabetes who are prone to low blood sugar learn to monitor levels frequently to keep blood sugar within normal ranges.
Hypoglycemia, National Institute of Diabetes, Digestive, and Kidney Diseases [NIDDK], National Institute of Health, Patient Publication
Taber's Cyclopedic Medical Dictionary, F.A. Davis Company, Philidelphia
Mayo Clinic Family Health Book, Mayo Foundation for Medical Education and Research, William Morrow and Company, New York, New York