Insulin is an essential hormone. It helps your body turn food into energy and controls your blood sugar levels. If you have diabetes, your body can’t make enough insulin or can’t use it properly. Your provider can prescribe human-made insulin that you take through an injection (shot), injectable pen or pump. You can also inhale insulin powder.
Insulin is a naturally occurring hormone made by your pancreas that helps your body use sugar for energy. If your pancreas doesn’t work as it should, it may not make or release the insulin you need to control your blood sugars, resulting in diabetes.
Diabetes is a condition in which your body doesn’t make enough insulin or your body doesn’t use insulin correctly.
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Insulin moves glucose from your blood into cells all over your body. Glucose comes from both food and your body’s own natural release of stored glucose. Think of insulin as the “key” that opens the “doors” of the cells in your body. Once insulin opens your cell doors, glucose can leave your bloodstream and move into your cells where you use it for energy. Without enough insulin, glucose can’t get into your cells and instead builds up in your blood (hyperglycemia).
Many conditions can affect your body’s ability to produce and release insulin. They include:
Your healthcare provider may prescribe insulin to lower your blood glucose and keep you healthy. We refer to the insulin available now as human insulin because it's made to act just like the insulin that’s naturally produced.
You can take insulin in a variety of ways based on your needs and lifestyle. Your healthcare team will work with you to determine which is best for you. You may:
Most types of insulin are injectable, either through a needle, pen or pump. There are many different types of injectable insulin. Your provider will work with you to prescribe the right type for you and adjust the dosage if your needs change. They will give you detailed instructions for giving yourself an insulin injection. A diabetes educator can help teach you how to take your insulin and guide you through the process.
Some types of insulin start to work quickly and wear off after a few hours. Providers call these types bolus or mealtime insulin because you may take them before a meal. Other types take longer to reach your bloodstream and work for as long as a day or two. Providers call these types basal or background insulin. Your provider may also prescribe a combination of basal and bolus called premixed insulin.
The main types are:
Some possible side effects of insulin include:
A note from Cleveland Clinic
Insulin is an essential hormone that helps you stay healthy and keeps your body working like it should. If your body isn’t able to make enough insulin, your provider can prescribe human-made insulin as a diabetes treatment. Follow your provider’s instructions carefully when giving yourself insulin. Call your provider or seek medical help right away if you have serious side effects from insulin. To stay healthy and lower your risk of insulin-related health problems, eat right, maintain a healthy weight and exercise regularly.
Last reviewed by a Cleveland Clinic medical professional on 03/07/2022.
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Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy