Overview
Blood glucose provides energy to cells and is normally kept within a fairly narrow range. Any deviation from the normal rage can lead to complications that are temporary or cause long-term health problems. Diabetics, people who have abnormally high blood glucose, can also have periods when their blood glucose drops abnormally low, called hypoglycemia. Nondiabetics can also have hypoglycemic reactions.
Types
Blood glucose levels can be either abnormally high or abnormally low. A range of 70 to 100 milligrams per deciliter (mg/dl) is normal after fasting for eight hours. Random blood glucose levels, taken at a time not dependent on the last time you ate, should not rise above 140 mg/dl. The definition of diabetes, or high blood glucose, is fasting blood sugar over 126 mg/dl on two separate occasions or nonfasting blood glucose over 200 mg/dl on two occasions, explains Nancy Morwessel, CNP, of the University of Cincinnati.
Abnormal glucose levels, sometimes called prediabetes, is fasting levels between 100 and 126 mg/dl and random blood glucose of between 140 and 200 mg/dl. Low blood sugar, or hypoglycemia, is less than 70 mg/dl at any time.
Significance
High blood glucose may be due to an especially high intake of carbohydrates, stress and certain medications, such as diuretics. Elevated levels can also indicate diabetes and require further investigation and treatment. Low glucose levels (hypoglycemia) can occur in diabetics who take too much insulin or who don’t eat regularly, as well as nondiabetics. People with hypoglycemia may have problems with the thyroid or pituitary glands, may have endocrine tumors or may be eating too little. People who produce an excess of insulin after eating may have reactive hypoglycemia, states the Mayo Clinic.
Symptoms
Moderately raised blood glucose levels are usually asymptomatic. Very high levels can cause hyperglycemic reactions, called diabetic ketoacidosis. Symptoms of hyperglycemia include a fruity smell on the breath, deep and rapid breathing, abdominal pain, dry mouth, excessive thirst, fatigue, coma, and, even, death, warns KidsHealth.org. Hypoglycemia can be equally dangerous. Symptoms include extreme hunger, dizziness, irritability, cold sweats, shakiness and tremors, coma, and, possibly, death.
Treatments
Diabetes requires regular observation, as well as medications to lower blood glucose. Type 1 diabetics, diabetics who don’t make insulin, must take insulin injections several times a day to facilitate uptake of glucose into cells. Type 2 diabetics, who make insulin but have cells resistant to using it or who need more than a normal amount of insulin, usually take oral hypoglycemic medicine everyday. A person in a hyperglycemic coma needs immediate medical attention and treatment in the hospital with intravenous insulin and fluids.
Reactive hypoglycemia is readily treated with sugar, which can be given by mouth or through an injection. People prone to reactive hypoglycemia should eat frequent, small meals that contain both protein and sugar. Diabetic hypoglycemia is treated by the same measures, plus an adjustment of diabetic medication. Other types of hypoglycemia are treated by correcting the cause.
Long-Term Complications
Abnormal blood glucose levels cause many complications. Diabetics whose glucose levels aren’t controlled well have damaged small blood vessels all over the body. Eye problems, kidney problems and heart and circulatory problems are all common in diabetics, according to MedlinePlus, and complications are worse in those with poor glucose control.
Low blood sugar doesn’t normally have long-term effects, but diabetics and others prone to hypoglycemia must always be aware of what they eat to ensure their blood sugars don’t drop suddenly.
About this Author
Sharon Perkins has worked as a registered nurse in oncology, labor/delivery, neonatal intensive care, infertility and ophthalmology. Perkins started writing professionally for the Wiley “Dummies” series in 2001, and has co-authored seven books for the series, and acted as developmental editor for several more. Perkins received her registered nursing degree from Western Oklahoma State College in 1986.
