Severe hypoglycemia: Dizziness, fatigue, weakness, headaches, inability to concentrate, confusion, slurred speech, blurred vision, seizures, and coma.

Some people develop symptoms at slightly higher levels, especially when blood glucose levels fall quickly, and some do not develop symptoms until the glucose levels in their blood are much lower. The body first responds to a fall in the level of glucose in the blood by releasing epinephrine from the adrenal glands.

Epinephrine is a hormone that stimulates the release of glucose from body stores but also causes symptoms similar to those of an anxiety attack: sweating, nervousness, shaking, faintness, palpitations, and hunger. More severe hypoglycemia reduces the glucose supply to the brain, causing dizziness, fatigue, weakness, headaches, inability to concentrate, confusion, inappropriate behavior that can be mistaken for drunkenness, slurred speech, blurred vision, seizures, and coma.

Severe and prolonged hypoglycemia may permanently damage the brain. Symptoms can begin slowly or suddenly, progressing from mild discomfort to severe confusion or panic within minutes.

Sometimes, people who have had diabetes for many years especially if they have had frequent episodes of hypoglycemia are no longer able to sense the early symptoms of hypoglycemia, and faintness or even coma may develop without any other warning.

In a person with an insulinoma Insulinoma An insulinoma is a rare type of tumor of the pancreas that secretes insulin, a hormone that lowers the levels of sugar glucose in the blood.

read more , symptoms are likely to occur early in the morning after an overnight fast, especially if the glucose stores in the blood are further depleted by exercise before breakfast.

At first, people with a tumor usually have only occasional episodes of hypoglycemia, but over months or years, episodes may become more frequent and severe.

In someone who is known to have diabetes, a doctor may suspect hypoglycemia when symptoms are described. The diagnosis may be confirmed when low glucose levels in the blood are measured while the person is experiencing symptoms.

In an otherwise healthy person who does not have diabetes, a doctor is usually able to recognize hypoglycemia based on the symptoms, medical history, a physical examination, and simple tests.

Doctors first measure the level of glucose in the blood. A low glucose level in the blood found at the time a person is experiencing typical symptoms of hypoglycemia confirms the diagnosis in a person without diabetes, especially if the relationship between a low glucose level in the blood and symptoms is demonstrated more than once.

If symptoms are relieved as the glucose levels in the blood rise within a few minutes of ingesting sugar, the diagnosis is supported. When the relationship between a person's symptoms and the level of glucose in the blood remains unclear in a person who does not have diabetes, additional tests may be needed.

Often, the next step is measurement of the glucose level in the blood after fasting in a hospital or other closely supervised setting. More extensive tests may also be needed. If use of a medication such as pentamidine or quinine is thought to be the cause of hypoglycemia, the medication is stopped and blood glucose levels are measured to determine if they increase.

If the cause remains unclear, other laboratory tests may be needed. If an insulinoma is suspected, measurements of insulin levels in the blood during fasting sometimes up to 72 hours may be needed. If the insulin levels are high and suggest a tumor, the doctor will try to locate it before treatment.

Sometimes a laboratory error such as when a blood sample is stored for too long can result in glucose levels that are artificially low, called pseudohypoglycemia. People prone to hypoglycemia should carry or wear medical identification to inform health care professionals of their condition.

The symptoms of hypoglycemia are relieved within minutes of consuming sugar in any form, such as candy, glucose tablets, or a sweet drink, such as a glass of fruit juice. People with recurring episodes of hypoglycemia, especially those with diabetes, often prefer to carry glucose tablets because the tablets take effect quickly and provide a consistent amount of sugar.

These people may benefit from consuming sugar followed by a food that provides longer-lasting carbohydrates such as bread or crackers. When hypoglycemia is severe or prolonged and taking sugar by mouth is not possible, doctors quickly give glucose intravenously to prevent brain damage.

People who are known to be at risk of episodes of severe hypoglycemia may keep glucagon on hand for emergencies.

Glucagon administration stimulates the liver to release large amounts of glucose. It is given by injection or by a nasal inhaler and generally restores blood glucose to an adequate level within 5 to 15 minutes.

Glucagon kits are easy to use, and family members or trusted others can be trained to administer the glucagon. Insulinomas Insulinoma An insulinoma is a rare type of tumor of the pancreas that secretes insulin, a hormone that lowers the levels of sugar glucose in the blood.

read more should be removed surgically. However, because these tumors are small and difficult to locate, a specialist should do the surgery. Before surgery, the person may be given a medication such as octreotide or diazoxide to control symptoms. Sometimes more than one tumor is present, and if the surgeon does not find them all, a second operation may be necessary.

People who do not have diabetes but are prone to hypoglycemia often can avoid episodes by eating frequent small meals rather than the usual three meals a day.

Limiting intake of carbohydrates, especially simple sugars, is sometimes advocated to prevent hypoglycemia that occurs after a meal called reactive hypoglycemia. Alpha-glucosidase inhibitors, such as acarbose , which slow the absorption of carbohydrates, have also been used successfully in people with reactive hypoglycemia and hypoglycemia after bariatric surgery.

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IN THIS TOPIC. OTHER TOPICS IN THIS CHAPTER. Hypoglycemia Low Blood Sugar By Erika F. GET THE QUICK FACTS. Causes Symptoms Diagnosis Treatment.

Adrenal glands to release cortisol. Pancreas to release glucagon. Medications Most cases of hypoglycemia occur in people with diabetes and are caused by insulin or other medications especially, sulfonylureas such as glyburide , glipizide , and glimepiride , see Medication Treatment of Diabetes Mellitus: Oral Antihyperglycemic Medications Oral Antihyperglycemic Medications Many people with diabetes require medication to lower blood glucose levels, relieve symptoms, and prevent complications of diabetes.

Mild hypoglycemia: Sweating, nervousness, shaking, faintness, palpitations, and hunger. Blood tests to measure glucose level. Did You Know? Consuming sugar to raise the level of glucose in the blood. If a medication is causing hypoglycemia, the dose is adjusted or the medication is changed.

Drugs Mentioned In This Article. Generic Name Select Brand Names glyburide. All rights reserved. You should talk with your doctor if you have any of these symptoms so you can manage gastroparesis and keep it from worsening.

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