All forms of insulin lower blood sugar levels, both by helping cells take up more glucose and, in the muscles and liver, by promoting the storage of that glucose as glycogen. In the liver, insulin also reduces the release of glucose into the blood plasma. In the past, insulin was extracted from animal pancreas tissue, but now virtually all insulin is made synthetically.
The available forms of insulin either are identical to human insulin or are insulin analogs, meaning that they have slight chemical changes designed to give them special properties. Insulins differ primarily in terms of how long after injection they reach their maximum, or peak, activity and their total duration of action. At present, all insulin available in the United States must be given by injection. Insulin is available in an individual form or premixed. Premixed insulins combine the intermediate-acting neutral protamine Hagedorn (NPH) insulin with a faster-acting insulin in the hope of providing the benefits of both types with a single injection.
Find out more about this book:The Best Life Guide to Managing Diabetes and Pre-Diabetes