Diabetes blood glucose levels
People with diabetes may have high blood glucose (hyperglycemia) or low blood glucose (hypoglycemia), and should learn to identify the associated symptoms. A cold, flu, or other sudden illness may cause high blood glucose. Insulin and some diabetes medications can cause hypoglycemia.
Knowing how to recognize and manage hyperglycemia and hypoglycemia can help avoid an emergency. For example, hyperglycemia can cause diabetic ketoacidosis or dehydration, and severe hypoglycemia can lead to loss of consciousness.
Most hyperglycemia or hypoglycemia can be managed at home according to your doctor’s instructions. Following your doctor’s instructions for insulin or diabetes medications, meals, and exercise can help prevent blood glucose problems. Home blood glucose testing helps to determine if blood glucose levels are within the target range.
Children with diabetes need help from their parents to keep their blood glucose levels in the target range and to exercise and be physically active while staying safe. Make sure the child understands the symptoms of high and low blood sugar and can tell others if he or she needs help.
Teenagers are growing, socialize a lot, and eat carelessly, and may have a harder time controlling their blood sugar levels. Although diabetes is not common in teens, teens should also learn about diabetes and its treatment and gradually begin to take responsibility for their own health.
If blood glucose levels are too high or too low, but you don’t feel uncomfortable, recheck your blood glucose levels or recalibrate your glucose meter. There may be a problem with the blood sample or the instrument.
High blood glucose (hyperglycemia)
Hyperglycemia occurs when the level of glucose in the blood is above the target range. Excessive calorie intake, missed medication (insulin or pills), an infection or illness, injury, surgery, or emotional stress can cause blood glucose to rise.
High blood sugar usually happens slowly over a few hours to a few days. But missing a single insulin dose can lead to a rapid rise in blood glucose levels. Blood glucose is above the target range, and patients may feel fatigue and thirst. If blood glucose is above the target range for a few weeks, the body will adapt and may not experience many symptoms of hyperglycemia.
If blood glucose levels are monitored regularly, or if symptoms of hyperglycemia are noted, there will be time to treat them and prevent a hyperglycemic emergency. Doing the following three things can help prevent hyperglycemia:
- Check your blood sugar often, especially if you are sick or not following your normal routine. Even if you don’t have symptoms such as thirst, excessive urination and fatigue, you may find that your blood sugar is above your target range.
- If high blood sugar occurs frequently, or if blood sugar levels are consistently above the target range, you need to seek medical help. Adjustments or changes in your medication regimen may be needed.
- Drink plenty of water or caffeine-free, sugar-free beverages to avoid dehydration. If blood sugar continues to rise, urine output will increase and dehydration may occur.
Complications from high blood sugar can lead to serious problems, including coma and death.
High blood sugar can gradually destroy the eyes, heart, kidneys, blood vessels, and nerves.
Low blood sugar (hypoglycemia)
Hypoglycemia occurs when the level of glucose in the blood drops below the amount your body needs.
Eating too little or no food, taking too much medicine (insulin or pills), exercising more than usual, or taking certain blood glucose-lowering medicines can cause a rapid drop in blood sugar. Do not drink alcohol if you cannot recognize the early signs of hypoglycemia.
For people who have lost weight or have kidney disease, less insulin or other medications may be needed than before. Check blood glucose levels often when a patient’s health changes.
Symptoms of hypoglycemia usually occur if blood glucose levels fall below 70 milligrams per deciliter (mg/dL) (that is, 3.9 mmol/L). Hypoglycemia occurs rapidly and can appear within 10 to 15 minutes.
- If blood glucose levels are only slightly below the target range (mild hypoglycemia), there may be symptoms such as fatigue, anxiety, weakness, shaking or sweating, and a faster heart rate. These symptoms may disappear quickly when you eat sugary foods at this time. People with diabetes may not always be aware of mild hypoglycemic symptoms, which is called asymptomatic hypoglycemia. If blood sugar is well controlled and does not change much throughout the day, asymptomatic hypoglycemia may be more likely to occur.
- If blood glucose levels continue to fall (usually below 40 mg/dL, or 2.2 mmol/L), the person may experience behavioral changes, such as irritability and irritability, or may feel weak or confused, or even be unable to eat sugary foods to raise blood glucose levels. Once blood glucose falls below 50 mg/dL, or 2.8 mmol/L, action should be taken regardless of the presence or absence of symptoms.
- If blood glucose levels fall to very low levels (usually below 20 mg/dL, or 1.1 mmol/L), you may lose consciousness or have a seizure. If symptoms of severe hypoglycemia occur, immediate medical attention is needed.
Symptoms of hypoglycemia may also occur if blood glucose levels drop from high to low. For example, if a patient’s blood glucose level has remained above 300 mg/dL (16.7 mmol/L) for a week and suddenly drops to 100 mg/dL (5.6 mmol/L), symptoms of hypoglycemia may occur even though the blood glucose is within the target range.
If you have had diabetes for many years, you may not have hypoglycemic symptoms unless your blood glucose level is extremely low.
Patients may be asked to check their blood glucose more often if their doctor thinks their blood glucose level is low but they are not experiencing symptoms. A midnight blood glucose check or a continuous 3-day check with a continuous glucose monitor may be ordered.