Analogue insulins are based on the human insulin molecule in which modifications have been made to either produce a faster onset and duration of action (such as aspart, lispro, glulisine) to or delay absorption and prolong duration of action (such as detemir and glargine). These modifications provide insulins that are better able to replicate endogenous basal and prandial insulin secretion. Both detemir and glargine have long durations of action with minimal peak, which decreases the risk of nocturnal hypoglycemia when compared to NPH insulin (Neutral Protamine Hagedorn insulin). The main downside of these medications is their cost.