"Novo Rapid (Insulin Aspart) has an onset of action about 30 minutes after injection and a peak effect at 1 hour with essentially no effect 3 hours after injection.
Blood glucose starts to rise less than 30 minutes after a meal, thus Novo Rapid is able to deal with this glucose rise earlier than Regular Insulin. As expected, there is less hyperglycemia 1 or 2 hours after a meal than there is using Regular Insulin and there is less hypoglycemia 3 to 4 hours after a meal than with Regular Insulin. In other words the action of Novo Rapid is closer to the action of food and it is therefore an effective insulin to take with meals."