Insulin is the hormone responsible for regulating your blood sugar. When you have diabetes, your body doesn't create enough insulin to keep your blood sugar under control. All people with type 1 diabetes, and many with type 2 diabetes, take insulin.
There are many different kinds of insulin preparations, including rapid–acting, short–acting, intermediate–acting, and long–acting. If you're taking insulin, it's important to know what type of insulin it is so you know how long it takes to be active (onset), when it is most active (peak), and how long it lasts (duration). You should take it exactly as prescribed unless directed by your primary care provider.
Many people with type 2 diabetes take oral medications, such as metformin, to help control their blood sugar levels. How well these medications work varies from person to person. Some people might need to take insulin in addition to an oral medication to keep blood sugar under control. Others might take a combination of different oral medications. Many people are able to reduce the amount of medication they need through diet and exercise, while some people are able to control their blood sugar with diet and exercise alone. But each person is different, so don't be discouraged if diet and exercise aren't enough for you.
Insulin and some oral medications can cause low blood sugars if taken incorrectly, if meals are missed, if the person gets more physical activity than usual, or if they are getting more medication than they need. It is important to let your primary care provider of diabetes educator know if you are experiencing low blood sugars.