This refers to the fast- or rapid-acting insulin diabetics use at mealtimes. Doing a curve on anyone will indicate how blood glucose levels rise after eating. This is called a post-prandial or post-meal spike; in humans, it commonly begins about 2 hours after food. The pancreas of a non-diabetic simply produces more insulin to handle the additional glucose. But diabetics cannot and so some take an additional or bolus insulin to manage the spike. For other uses of an extra, insulin in addition to use as a bolus, see booster.