Patient education: Using insulin (The Basics)

What is insulin? — Insulin is a medicine that many people with diabetes use as part of their treatment. Diabetes is a disorder that disrupts the way a person's body uses sugar. This causes sugar to build up in the blood.

Insulin can lower a person's blood sugar level. It usually comes as a shot that you give yourself.

Are there different types of insulin? — Yes. All types of insulin can control blood sugar levels. But some types of insulin start working faster or last longer than other types. Many people use 2 different types of insulin each day so that their body has insulin all day and night.

How many times a day should I use insulin? — It depends. Your doctor will work with you to make a treatment plan that tells you:

●When to use insulin

●What type of insulin to use

●How much insulin to use

Some people use the same amount of insulin 1 or 2 times a day, at the same time each day. But many people use insulin 3 or more times a day, usually before each meal. Using insulin 3 or more times a day can control a person's blood sugar level better.

How much insulin should I use? — Sometimes, people need to choose their dose of insulin. When choosing how much insulin to use, you need to think about:

●What you plan to eat at the next meal

●How much exercise you plan to do

●What your blood sugar level is

Also, you will probably need to change your insulin dose if you:

●Have surgery, get sick, or get pregnant

●Eat out or travel

●Gain or lose weight

Ask your doctor or nurse how to change your insulin dose during these times.

How do I give myself an insulin shot? — Your doctor or nurse will teach you how to give yourself an insulin shot. You will need either a prefilled insulin pen injector, or a needle and syringe to draw up insulin from a small bottle.

The pen injectors are easier to use than the older syringes and insulin bottles. They have prefilled insulin cartridges and a needle (figure 1). There is a knob at the end of the pen, which you can turn to mark the number of units you need to take. If you cannot turn the knob to set a dose, there is not enough insulin left in the pen. When this happens, start a new pen.

If you use a bottle and syringe, make sure that you use the correct syringe for your type of insulin. Using the wrong syringe with your insulin can cause a dangerous insulin overdose.

Whether you are using an injector pen or a syringe, you give yourself the insulin shot in the same way:

●Choose a part of the body. You can use different parts of the body for an insulin shot (figure 2). Switch or "rotate" areas each time you give yourself a shot.

●Pinch up some skin, and quickly insert the needle (figure 3).

●Push the plunger down all of the way, and count to 5.

●Let go of the skin, and remove the needle.

●Throw away the needle in a container that is made for used needles. If you used a syringe, throw this away, too.

Never use another person's insulin pen (even if the needle is changed) or let another person use yours.

What is an insulin pump? — An insulin pump is a device that slowly releases insulin into the body. The insulin goes through a thin tube from the pump into the body through an opening in the skin (figure 4). The device keeps working all day and night.

What is inhaled insulin? — Inhaled insulin is an insulin powder that is breathed into the lungs. The insulin powder comes in a cartridge that can be placed into a small inhaler (like an asthma inhaler). Place the inhaler into your mouth, and when you breathe in, the powdered insulin goes into your lungs.

Most people with diabetes use insulin shots or a pump rather than inhaled insulin.

How do I know if I am using the right amount of insulin? — To know if you are using the right amount of insulin, check your blood sugar level at home. Most doctors recommend that people who use insulin with each meal check their blood sugar level at least 4 times a day.

Why do I need to check my blood sugar level? — Checking your blood sugar level is important because it can tell you:

●If your blood sugar level gets too low or too high – If you use too much insulin, your blood sugar level can get too low. If you do not use enough insulin, your blood sugar level can get too high. Levels that are too low or too high can lead to serious problems. Talk with your doctor or nurse about what to do if your blood sugar level gets too low or too high.

●What changes to make in your next insulin dose – Knowing your blood sugar level will help you choose your next insulin dose.

●How well your treatment is working – One goal of diabetes treatment is to keep your blood sugar at or near your goal level. This can prevent health problems later in life.

How do I check my blood sugar level at home? — You can use a "blood glucose monitor" or a "continuous glucose monitor" ("CGM") to check your blood sugar level. Most people who use insulin can use either type of device. Your doctor or nurse will show you how to use your device.

In general:

●Most blood glucose monitors work the same way. You prick your skin to get a drop of blood. Many people prick their fingertips (picture 1), but you can prick other parts of the body (picture 2). Then, put the drop of blood into the monitor. After a few seconds, the monitor shows your blood sugar level.

●CGM devices measure your sugar level all of the time. With CGM, you wear a special sensor that attaches to your skin with a sticky patch (figure 5 and figure 6). It measures the sugar in the fluid under your skin. Then, it sends the information to a small box that can attach to your clothing or go in a bag. One type of CGM device can be placed under the skin and used for up to 6 months. For this type, a doctor does a minor procedure to insert the device.

If you use CGM, you might still need to check your blood sugar by pricking your skin. This is especially important when your sugar levels are changing quickly, or if you think that your monitor might not be working correctly. When and how often to do this depends on which device you use.

More on this topic

Patient education: Type 1 diabetes (The Basics)
Patient education: Type 2 diabetes (The Basics)
Patient education: Treatment for type 2 diabetes (The Basics)
Patient education: Low blood sugar in people with diabetes (The Basics)
Patient education: Managing blood sugar in children with diabetes (The Basics)
Patient education: Giving your child insulin (The Basics)
Patient education: Checking your child's blood sugar level (The Basics)
Patient education: Should I switch to an insulin pump? (The Basics)
Patient education: How to use an insulin pen (The Basics)
Patient education: How to give an insulin shot (The Basics)
Patient education: How to dispose of needles and other sharps (The Basics)

Patient education: Type 1 diabetes: Insulin treatment (Beyond the Basics)
Patient education: Glucose monitoring in diabetes (Beyond the Basics)
Patient education: Type 2 diabetes: Insulin treatment (Beyond the Basics)
Patient education: Type 2 diabetes: Treatment (Beyond the Basics)