Hypoglycemia
Hypoglycemic symptoms and manifestations can be divided into those produced by the counterregulatory hormones (epinephrine/adrenaline and glucagon) triggered by the falling glucose, and the neuroglycopenic effects produced by the reduced brain sugar.Not all of the above manifestations occur in every case of hypoglycemia. There is no consistent order to the appearance of the symptoms, if symptoms even occur. Specific manifestations may also vary by age, by severity of the hypoglycemia and the speed of the decline. In young children, vomiting can sometimes accompany 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 may be similar from episode to episode, but are not necessarily so and may be influenced by the speed at which glucose levels are dropping, as well as previous incidents.
Hyperinsulinemic hypoglycemia
Hyperinsulinemic hypoglycemia describes the condition and effects of low blood glucose caused by excessive insulin. Hypoglycemia due to excess insulin is the most common type of serious hypoglycemia. It can be due to endogenous or injected insulin.
Manifestations of hyperinsulinemic hypoglycemia vary by age and severity of the hypoglycemia. In general, most signs and symptoms can be attributed to (1) the effects on the brain of insufficient glucose (neuroglycopenia) or (2) to the adrenergic response of the autonomic nervous system to hypoglycemia. A few miscellaneous symptoms are harder to attribute to either of these causes. In most cases, all effects are reversed when normal glucose levels are restored.