Doctors

Hypoglycemia (Low Blood Sugar) is a medical term referring to a pathologic state produced and usually defined by a lower than normal amount of sugar (glucose) in the blood. The term hypoglycemia literally means "low blood sugar". Hypoglycemia can produce a variety of symptoms and effects but the principal problems arise from an inadequate supply of glucose as fuel to the brain, resulting in impairment of function (neuroglycopenia). Derangements of function can range from vaguely "feeling bad" to coma and (rarely) death. Low blood sugar can arise from many conditions, and can occur at any age.

Endocrinologists (specialists in disorders of blood glucose metabolism) typically consider the following criteria (referred to as Whipple's triad) as confirming a diagnosis of hypoglycemia (low blood sugar):

• Measurably low level of blood glucose
• Presence of symptoms or problems at the time of the low glucose
• Reversal or improvement of symptoms or problems when the glucose is restored to normal

symptoms of hypoglycemia - low blood sugar symptoms

Hypoglycemic symptoms and manifestations can be divided into those produced by the counterregulatory hormones (adrenaline and glucagon) triggered by the falling glucose, and the neuroglycopenic effects produced by the reduced brain sugar.

Adrenergic Manifestations of low blood sugar symptoms

• Shakiness, anxiety, nervousness, tremor
• Palpitations, tachycardia
• Sweating, feeling of warmth
• Pallor, coldness, clamminess
• Dilated pupils

Glucagon Manifestations of hypoglycemia symptoms

• Hunger, borborygmus
• Nausea, vomiting, abdominal discomfort

Neuroglycopenic Manifestations of hypoglycemia symptoms

• Abnormal mentation, impaired judgement
• Nonspecific dysphoria, anxiety, moodiness, depression, crying, fear of dying
• Negativism, irritability, belligerence, combativeness, rage
• Personality change, emotional lability
• Fatigue, weakness, apathy, lethargy, daydreaming, sleep
• Confusion, amnesia, dizziness, delirium
• Staring, "glassy" look, blurred vision, double vision
• Automatic behavior
• Difficulty speaking, slurred speech
• Ataxia, incoordination, sometimes mistaken for "drunkenness"
• Focal or general motor deficit, paralysis, hemiparesis
• Paresthesias, headache
• Stupor, coma, abnormal breathing
• Generalized or focal seizures

Not all of the above manifestations occur in every case of hypoglycemia. There is no consistent order to the appearance of the symptoms. Specific manifestations vary by age and by the severity of the hypoglycemia. In young children vomiting often accompanies morning hypoglycemia with ketosis. In older children and adults, moderately severe hypoglycemia can resemble mania, mental illness, drug intoxication, or drunkenness. In the elderly, hypoglycemia can produce focal stroke-like effects or a hard-to-define malaise. The symptoms of a single person do tend to be similar from episode to episode.

In newborns, hypoglycemia can produce irritability, jitters, myoclonic jerks, cyanosis, respiratory distress, apneic episodes, sweating, hypothermia, somnolence, hypotonia, refusal to feed, and seizures or "spells". Hypoglycemia can resemble asphyxia, hypocalcemia, sepsis, or heart failure.

In both young and old patients, the brain may habituate to low glucose levels, with a reduction of noticeable symptoms despite neuroglycopenic impairment. In insulin-dependent diabetic patients this phenomenon is termed hypoglycemia unawareness and is a significant clinical problem when improved glycemic control is attempted. Another aspect of this phenomenon occurs in type I glycogenosis, when chronic hypoglycemia before diagnosis may be better tolerated than acute hypoglycemia after treatment is underway.

In the large majority of cases, hypoglycemia severe enough to cause seizures or unconsciousness can be reversed without obvious harm to the brain. Cases of death or permanent neurologic damage occurring with a single episode have usually involved prolonged, untreated unconsciousness, interference with breathing, severe concurrent disease, or some other type of vulnerability. Nevertheless, brain damage or death has occasionally resulted from severe hypoglycemia.