MODEL RELEASED. Insulin injection. Teacher watching a diabetic schoolgirl inject herself in the thigh with an insulin pen. The child has diabetes mellitus, a disorder affecting glucose sugar metabolism. Sugar is not oxidised due to a lack of the pancreatic hormone insulin and unused sugar builds up in the blood and the urine. Fats are used as an alternative energy source, which leads to an accumulation of ketones in the blood that may eventually cause convulsions and diabetic coma. Treatment is based on a strict diet and the use of daily insulin injections to maintain the blood-sugar balance.