People with diabetes may experience low blood sugar as often as once or twice a week, even when managing their blood sugar closely. Knowing how to identify and treat it is important for your health. Learn how to treat low blood sugar.

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You may need to check your blood sugar more often. Causes of Low Blood Sugar There are many reasons why you may have low blood sugar, including: Taking too much insulin. Not eating enough carbs for how much insulin you take.

Timing of when you take your insulin. The amount and timing of physical activity. Drinking alcohol. How much fat, protein, and fiber are in your meal. Hot and humid weather. Unexpected changes in your schedule. Spending time at a high altitude. Going through puberty. Symptoms of Low Blood Sugar How you react to low blood sugar may not be the same as how someone else with low blood sugar reacts.

Common symptoms may include: Fast heartbeat Shaking Sweating Nervousness or anxiety Irritability or confusion Dizziness Hunger. Hypoglycemia Unawareness.

This is more likely to happen if you: Have had diabetes for more than years. Frequently have low blood sugar.

Take certain medicines, such as beta blockers for high blood pressure. Types of Low Blood Sugar Nighttime low blood sugar While low blood sugar can happen at any time during the day, some people may experience low blood sugar while they sleep.

Reasons this may happen include: Having an active day. Being physically active close to bedtime. Taking too much insulin. Drinking alcohol at night. Severe low blood sugar As your low blood sugar gets worse, you may experience more serious symptoms, including: Feeling weak.

Having difficulty walking or seeing clearly. Each person's reaction to hypoglycemia is different. As unpleasant as they may be, these symptoms are useful as they help let you know that action is needed to correct a low blood sugar.

This is called hypoglycemia unawareness. People with hypoglycemia unawareness are not able to tell when their blood sugar goes too low and may need help from someone else to treat it — this is also known as a severe low.

If you or someone you know has hypoglycemia unawareness, it is important to check blood sugar frequently or wear a continuous glucose monitor CGM. This is important for critical tasks such as driving.

The only CGM that can alert up to an hour before a high or low so that people with diabetes can get ahead of their lows. The American Diabetes Association Page. Accessed 1SEP 2 The system is intended to complement, not replace, information obtained from standard blood glucose monitoring devices.

All therapy adjustments should be based on measurements obtained from standard blood glucose monitoring devices. All therapy adjustments should be based on measurements obtained using a home blood glucose meter and not on values provided by the system.

Reactive hypoglycemia occurs within a few hours after a meal. An overproduction of insulin causes reactive hypoglycemia.

Causes of nonreactive, or fasting, hypoglycemia include:. Although rare, a tumor of the pancreas can cause the body to make too much insulin or an insulin-like substance, resulting in hypoglycemia. Hormone deficiencies can also cause hypoglycemia because hormones control blood sugar levels.

Dumping syndrome also occurs in patients who have had gastric bypass surgery. In late dumping syndrome, the body releases excess insulin in response to carbohydrate-rich meals.

That can result in hypoglycemia and related symptoms. If you have diabetes, there are several reasons you may experience hypoglycemia. Causes of hypoglycemia include:. Causes of hypoglycemia without diabetes include:. Hypoglycemia without diabetes can occur in both children and adults.

Your doctor will need to identify the cause of your hypoglycemia to determine the right long-term therapy for you. Glucose will help boost your blood sugar levels in the short term. One way to get additional glucose is to consume 15 grams of carbohydrates.

Drinking fruit juice is an easy way to get extra glucose into your bloodstream. These sources of glucose often briefly correct hypoglycemia, but then another drop in blood sugar often follows.

Eating foods that are high in complex carbohydrates , such as pasta and whole grains, will sustain blood sugar levels after a period of hypoglycemia. Symptoms of hypoglycemia can become so severe that they interfere with daily routines and activities.

If you have severe hypoglycemia, you might need to carry glucose tablets or injectable glucose glucagon. Your doctor may ask you to take a fasting test. This test can last as long as 72 hours. Another test is a mixed-meal tolerance test. This test is for people who experience hypoglycemia after eating.

The results are usually available within a day or two. Keep track of your symptoms with a symptom diary. This information will help your doctor make a diagnosis. Your body needs glucose to function. Without the right level of glucose, your body will struggle to perform its normal functions. As a result, you may have difficulty thinking clearly and performing even simple tasks.

In severe cases, hypoglycemia can lead to seizures , neurological problems that may mimic a stroke , or even loss of consciousness. For this reason, you may not realize that your blood sugar levels have dropped, which can make you more susceptible to severe symptoms of hypoglycemia, including confusion, loss of consciousness, or seizures.

If you think that you may have hypoglycemia unawareness, talk with your doctor to determine the best course of treatment. This may include checking your blood sugar levels more frequently, adjusting your medications, or working with a certified diabetes educator to learn to recognize the warning signs of hypoglycemia.

Having low blood sugar levels can increase your risk of many conditions, including heart disease. In fact, research shows that severe hypoglycemia could be linked to a higher risk of heart disease and death in people with type 2 diabetes.

If left untreated, hypoglycemia can have several serious side effects. Severe complications of hypoglycemia include :. Simple changes to your diet and eating schedule can resolve hypoglycemia and prevent future episodes.

Follow these tips to prevent hypoglycemia:. Eating consistently and following a healthy, well-rounded diet are also crucial. Insulin pumps may also reduce the risk for low blood glucose.

Accidentally injecting the wrong insulin type, too much insulin, or injecting directly into the muscle instead of just under the skin , can cause low blood glucose.

Exercise has many benefits. The tricky thing for people with type 1 diabetes is that it can lower blood glucose in both the short and long-term. Nearly half of children in a type 1 diabetes study who exercised an hour during the day experienced a low blood glucose reaction overnight.

The intensity, duration, and timing of exercise can all affect the risk for going low. Many people with diabetes, particularly those who use insulin, should have a medical ID with them at all times. In the event of a severe hypoglycemic episode, a car accident or other emergency, the medical ID can provide critical information about the person's health status, such as the fact that they have diabetes, whether or not they use insulin, whether they have any allergies, etc.

Emergency medical personnel are trained to look for a medical ID when they are caring for someone who can't speak for themselves. Medical IDs are usually worn as a bracelet or a necklace.

Traditional IDs are etched with basic, key health information about the person, and some IDs now include compact USB drives that can carry a person's full medical record for use in an emergency.

As unpleasant as they may be, the symptoms of low blood glucose are useful. These symptoms tell you that you your blood glucose is low and you need to take action to bring it back into a safe range. But, many people have blood glucose readings below this level and feel no symptoms.

This is called hypoglycemia unawareness. Hypoglycemia unawareness puts the person at increased risk for severe low blood glucose reactions when they need someone to help them recover.

People with hypoglycemia unawareness are also less likely to be awakened from sleep when hypoglycemia occurs at night. People with hypoglycemia unawareness need to take extra care to check blood glucose frequently.

This is especially important prior to and during critical tasks such as driving. A continuous glucose monitor CGM can sound an alarm when blood glucose levels are low or start to fall.

This can be a big help for people with hypoglycemia unawareness. If you think you have hypoglycemia unawareness, speak with your health care provider. This helps your body re-learn how to react to low blood glucose levels.

This may mean increasing your target blood glucose level a new target that needs to be worked out with your diabetes care team. It may even result in a higher A1C level, but regaining the ability to feel symptoms of lows is worth the temporary rise in blood glucose levels. This can happen when your blood glucose levels are very high and start to go down quickly.

If this is happening, discuss treatment with your diabetes care team. Your best bet is to practice good diabetes management and learn to detect hypoglycemia so you can treat it early—before it gets worse. Monitoring blood glucose, with either a meter or a CGM, is the tried and true method for preventing hypoglycemia.

Studies consistently show that the more a person checks blood glucose, the lower his or her risk of hypoglycemia. This is because you can see when blood glucose levels are dropping and can treat it before it gets too low.

Together, you can review all your data to figure out the cause of the lows. The more information you can give your health care provider, the better they can work with you to understand what's causing the lows. However, this approach isn't advised as a long-term strategy.

Work with your health care provider to identify and treat the cause of hypoglycemia. Mayo Clinic does not endorse companies or products.

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This content does not have an English version. This content does not have an Arabic version. Overview Hypoglycemia is a condition in which your blood sugar glucose level is lower than the standard range. Request an appointment. Thank you for subscribing!

Sorry something went wrong with your subscription Please, try again in a couple of minutes Retry. Continuous glucose monitor and insulin pump Enlarge image Close. Continuous glucose monitor and insulin pump A continuous glucose monitor, on the left, is a device that measures your blood sugar every few minutes using a sensor inserted under the skin.

By Mayo Clinic Staff. Show references AskMayoExpert. Unexplained hypoglycemia in a nondiabetic patient. Mayo Clinic; American Diabetes Association. Standards of medical care in diabetes — Diabetes Care. Accessed Nov. Hypoglycemia low blood sugar.

Low blood glucose hypoglycemia. National Institute of Diabetes and Digestive and Kidney Diseases. Cryer PE. Hypoglycemia in adults with diabetes mellitus.

Vella A. Hypoglycemia in adults without diabetes mellitus: Clinical manifestations, diagnosis, and causes. Merck Manual Professional Version.

What is diabetes? Centers for Disease Control and Prevention. Kittah NE, et al. Management of endocrine disease: Pathogenesis and management of hypoglycemia. European Journal of Endocrinology. Vella A expert opinion. Mayo Clinic. Castro MR expert opinion. Mayo Clinic Press Check out these best-sellers and special offers on books and newsletters from Mayo Clinic Press.

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