Hypoglycemia, also called low blood sugar, occurs when your blood glucose (blood sugar) level drops too low to provide enough energy for your body's activities. In adults or children older than 10 years, hypoglycemia is uncommon except as a side effect of diabetes treatment, but it can result from other medications or diseases, hormone or enzyme deficiencies, or tumors.
Glucose, a form of sugar, is an important fuel for your body. Carbohydrates are the main dietary sources of glucose. Rice, potatoes, bread, tortillas, cereal, milk, fruit, and sweets are all carbohydrate-rich foods.
After a meal, glucose molecules are absorbed into your bloodstream and carried to the cells, where they are used for energy. Insulin, a hormone produced by your pancreas, helps glucose enter cells. If you take in more glucose than your body needs at the time, your body stores the extra glucose in your liver and muscles in a form called glycogen. Your body can use the stored glucose whenever it is needed for energy between meals. Extra glucose can also be converted to fat and stored in fat cells.
When blood glucose begins to fall, glucagon, another hormone produced by the pancreas, signals the liver to break down glycogen and release glucose, causing blood glucose levels to rise toward a normal level. If you have diabetes, this glucagon response to hypoglycemia may be impaired, making it harder for your glucose levels to return to the normal range.
What is the Symptoms of hypoglycemia?
Symptoms of hypoglycemia include:
- hunger
- nervousness and shakiness
- perspiration
- dizziness or light-headedness
- sleepiness
- confusion
- difficulty speaking
- feeling anxious or weak
Hypoglycemia can also happen while you are sleeping. You might
- cry out or have nightmares
- find that your pajamas or sheets are damp from perspiration
- feel tired, irritable, or confused when you wake up
Hypoglycemia: A Side Effect of Diabetes Medications
Hypoglycemia can occur in people with diabetes who take certain medications to keep their blood glucose levels in control. Usually hypoglycemia is mild and can easily be treated by eating or drinking something with carbohydrate. But left untreated, hypoglycemia can lead to loss of consciousness. Although hypoglycemia can happen suddenly, it can usually be treated quickly, bringing your blood glucose level back to normal.
What is the causes of Hypoglycemia?
In people taking certain blood-glucose lowering medications, blood glucose can fall too low for a number of reasons:
- meals or snacks that are too small, delayed, or skipped
- excessive doses of insulin or some diabetes medications, including sulfonylureas and meglitinides (Alpha-glucosidase inhibitors, biguanides, and thiazolidinediones alone should not cause hypoglycemia but can when used with other diabetes medicines.)
- increased activity or exercise
- excessive drinking of alcohol
Treatment of hypoglycemia?
If you think your blood glucose is too low, use a blood glucose meter to check your level. If it is 70 mg/dL or below, have one of these "quick fix" foods right away to raise your blood glucose:
- 2 or 3 glucose tablets
- 1/2 cup (4 ounces) of any fruit juice
- 1/2 cup (4 ounces) of a regular (not diet) soft drink
- 1 cup (8 ounces) of milk
- 5 or 6 pieces of hard candy
- 1 or 2 teaspoons of sugar or honey
After 15 minutes, check your blood glucose again to make sure that it is no longer too low. If it is still too low, have another serving. Repeat these steps until your blood glucose is at least 70. Then, if it will be an hour or more before your next meal, have a snack.
If you take insulin or a diabetes medication that can cause hypoglycemia, always carry one of the quick-fix foods with you. Wearing a medical identification bracelet or necklace is also a good idea.
Exercise can also cause hypoglycemia. Check your blood glucose before you exercise.
Severe hypoglycemia can cause you to lose consciousness. In these extreme cases when you lose consciousness and cannot eat, glucagon can be injected to quickly raise your blood glucose level. Ask your health care provider if having a glucagon kit at home and at work is appropriate for you. This is particularly important if you have type 1 diabetes. Your family, friends, and co-workers will need to be taught how to give you a glucagon injection in an emergency.
Prevention of hypoglycemia while you are driving a vehicle is especially important. Checking blood glucose frequently and snacking as needed to keep your blood glucose above 70 mg/dL will help prevent accidents.
Who is at risk for hypoglycemia?
While patients who do not have any metabolic problems can complain of symptoms suggestive of low blood sugar, true hypoglycemia usually occurs in patients being treated for diabetes (type 1 and type 2). Patients with pre-diabetes who have insulin resistance can also have low sugars on occasion if their high circulating insulin levels are further challenged by a prolonged period of fasting. There are other rare causes for hypoglycemia, such as insulin producing tumors (insulinomas) and certain medications. These uncommon causes of hypoglycemia will not be discussed in this article, which will primarily focus on the hypoglycemia occurring with diabetes mellitus and its treatment.
Despite our advances in the treatment of diabetes, hypoglycemic episodes are often the limiting factor in achieving optimal blood sugar control. In large scale studies looking at tight control in both type 1 and type 2 diabetes, low blood sugars occurred more often in the patients who were managed most intensively. This is important for patients and physicians to recognize, especially as the goal for treating patients with diabetes become tighter blood sugar control.
