Hypoglycemia (low blood sugar) and hyperglycemia (elevated blood sugar levels) are acute complications that can occur particularly in diabetics treated with insulin.

Hypoglycemia (“hypo”) is defined as a drop in blood sugar below 50 mg/dL (= 2.7 mmol/L). A distinction is made between mild hypoglycemia, which affected individuals can treat themselves by ingesting glucose, and severe hypoglycemia, which requires assistance from others. Severe hypoglycemia is dangerous because it can be accompanied by loss of consciousness (coma) and can therefore pose a risk to the individual and—depending on the situation (e.g., driving)—to others.

Hyperglycemia is present when blood sugar levels rise above the normal range (> 200 mg/dL or 11.1 mmol/L). If left untreated, hyperglycemia can develop into ketosis or ketoacidosis (a dangerous metabolic derangement).

Hypoglycemia (Low Blood Sugar)
Hyperglycemia (elevated blood sugar levels), ketoacidosis, and coma