Your body changes carbohydrates in the food you eat into glucose (a form of sugar). Insulin is a hormone produced by the pancreas that allows glucose to enter all the cells of your body and be used as energy.
Diabetes is a disease that occurs when a person's body doesn't make enough insulin or can't use insulin properly. When you have diabetes, the sugar builds up in your blood instead of moving into the cells. Too much sugar in the blood can lead to serious health problems, including heart disease and damage to the nerves and kidneys.
There are 2 types of diabetes. Type 1 diabetes occurs when the body doesn't produce any insulin. In type 2 diabetes, the body either doesn't produce enough insulin or the cells ignore the insulin. Between 90-95% of people who are diagnosed with diabetes have type 2 diabetes.
Diabetes: Insulin Basics
What is diabetes?
Why do I need to take insulin?
All people who have type 1 diabetes and some people who have type 2 diabetes need to take insulin to help control their blood sugar levels.
The goal of taking insulin is to keep your blood sugar level in a normal range as much as possible so you'll stay healthy. Insulin can't be taken by mouth. It is usually taken with injections (shots). It can also be taken with an insulin pen or an insulin pump.
The goal of taking insulin is to keep your blood sugar level in a normal range as much as possible so you'll stay healthy. Insulin can't be taken by mouth. It is usually taken with injections (shots). It can also be taken with an insulin pen or an insulin pump.
How often will I need to take insulin?
You and your doctor will develop a schedule that is right for you. Most people who have diabetes and take insulin need at least 2 insulin shots a day for good blood sugar control. Some people need 3 or 4 shots a day.
Do I need to monitor my blood sugar level?
Yes. Monitoring and controlling your blood sugar is key to preventing the complications of diabetes. If you don't already monitor your blood sugar level, you will need to learn how. Checking your blood sugar involves pricking your finger to get a small drop of blood that you put on a test strip. You can read the results yourself or insert the strip into a machine called an electronic glucose meter. The results will tell you whether or not your blood sugar is in a healthy range. Your doctor will give you additional information about monitoring your blood sugar.
When should I take insulin?
You and your doctor should discuss when and how you will take your insulin. Each person's treatment is different. Some people who use regular insulin take it 30 to 60 minutes before a meal. Some people who use rapid-acting insulin take it just before they eat.
Types of insulin
Rapid-acting insulin (such as insulin lispro, insulin aspart and insulin glulisine) starts working in 5 to 15 minutes. Insulin lispro and insulin aspart last 2 to 5 hours. Insulin glulisine lasts for 60 to 90 minutes.
Short-acting insulin (such as regular insulin) starts working in 30 to 60 minutes and lasts about 8 to 12 hours.
Intermediate-acting insulin (such as insulin NPH) starts working in 60 to 90 minutes and lasts up to 24 hours.
Long-acting insulin (such as insulin glargine and insulin detemir) starts working within 1 to 2 hours and lasts up to 24 hours.
Premixed insulin is a combination of 2 types of insulin (usually a rapid- or short-acting insulin and an intermediate-acting insulin)
Short-acting insulin (such as regular insulin) starts working in 30 to 60 minutes and lasts about 8 to 12 hours.
Intermediate-acting insulin (such as insulin NPH) starts working in 60 to 90 minutes and lasts up to 24 hours.
Long-acting insulin (such as insulin glargine and insulin detemir) starts working within 1 to 2 hours and lasts up to 24 hours.
Premixed insulin is a combination of 2 types of insulin (usually a rapid- or short-acting insulin and an intermediate-acting insulin)
Where should I inject the insulin?
Picture 1. Pull back on the plunger to draw insulin into the syringe.
The usual places to inject insulin are the upper arm, the front and side of the thighs, and the abdomen. Inject insulin at least 2 inches away from your belly button. Ask your doctor which place you should use. Insulin injected near the stomach works fastest, while insulin injected into the thigh works slowest. Insulin injected into the arm works at medium speed.
To keep your skin from thickening, try not to inject insulin in the same place over and over. Instead, rotate injection places.
To keep your skin from thickening, try not to inject insulin in the same place over and over. Instead, rotate injection places.
How do I take insulin?
Insulin is normally injected under the skin with a very small needle. It can also be taken with an insulin pen. Your doctor will teach you how to inject insulin. Follow your doctor's instructions. The following are some general tips on using insulin:
Picture 2. Clean the injection area using cotton and alcohol (top). Pinch an area of skin and inject insulin (bottom).
- Wash your hands.
- Take the plastic cover off of the insulin bottle and wipe the top of the bottle with a cotton swab that you have dipped in alcohol.
- Pull back the plunger of the syringe, drawing air into the syringe equal to the dose of insulin that you are taking (measured in units). Put the syringe needle through the rubber top of the insulin bottle. Inject air into the bottle by pushing the syringe plunger forward. Turn the bottle upside down.
- Make sure that the tip of the needle is in the insulin. Pull back on the syringe plunger to draw the correct dose of insulin into the syringe (PICTURE 1).
- Make sure there are no air bubbles in the syringe before you take the needle out of the insulin bottle. If there are air bubbles, hold the syringe and the bottle straight up, tap the syringe with your finger and let the air bubbles float to the top. Push on the plunger of the syringe to move the air bubbles back into the insulin bottle. Then withdraw the correct insulin dose by pulling back on the plunger.
- Clean your skin with cotton dipped in alcohol (PICTURE 2, top). Grab a fold of skin and inject the insulin at a 90-degree angle (PICTURE 2, bottom). (If you're thin, you may need to pinch the skin and inject the insulin at a 45-degree angle.)
What happens if I take too much insulin?
If you take too much insulin it will lower your blood sugar level too much, and you may get hypoglycemia (also called an insulin reaction). Signs of hypoglycemia include the following:
- Feeling very tired
- Frequent yawning
- Being unable to speak or think clearly
- Loss of muscle coordination
- Sweating
- Twitching
- Seizures
- Suddenly feeling like you're going to pass out
- Becoming very pale
- Loss of consciousness
People who have diabetes should carry at least 15 grams of a fast-acting carbohydrate with them at all times in case of hypoglycemia. The following are examples of quick sources of energy that can relieve the symptoms:
- Nondiet soda: ½ to ¾ cup
- Fruit juice: ½ cup
- Fruit: 2 tablespoons of raisins
- Milk: 1 cup
- Candy: 5 Lifesavers
- Glucose tablets: 3 tablets (5 grams each)
If you don't feel better 15 minutes after having a fast-acting carbohydrate, or if monitoring shows that your blood sugar level is still too low, have another 15 grams of a fast-acting carbohydrate.
Source
Written by familydoctor.org editorial staff.
American Academy of Family Physicians
Reviewed/Updated: 05/09
Created: 09/00