Insulin Treatment in Diabetes

Diabetes is a lasting (chronic) disease. It occurs when the body does not properly use the sugar (glucose) that is released from food. Glucose levels are controlled by a hormone called insulin, which is made by your pancreas. Depending on the type of diabetes you have, either:

  • The pancreas does not make any insulin (type 1 diabetes).

  • The pancreas makes too little insulin, and the body cannot respond normally to the insulin that is made (type 2 diabetes).

Without insulin, death can occur. Diabetes requires lifelong monitoring and treatment. This document will discuss the role of insulin in your treatment and provide information about insulin.


Lifestyle choices can affect both the control of your diabetes and your risk of complications from diabetes. Lifestyle choices are critically important in the overall management of diabetes. They are important even if you do not need to take insulin.

  • Eat a healthy diet. Ask for help if you need it.

  • Exercise regularly. Ask for help if you need it.

  • Diet and exercise can help:

  • Reduce the amount of insulin you need.

  • Your body to use your insulin more effectively.

  • Reduce your risk of high blood pressure (or reduce your blood pressure, if it is high).

  • Reduce your cholesterol level.

  • Reduce your weight.

Healthy lifestyle choices play an important role in controlling cardiovascular disease (heart attack, stroke, vascular disease, and others), which is a primary complication of diabetes. For optimal control of diabetes, you must reduce your cardiovascular risks and manage your blood sugar.


Your caregiver may recommend medicines for you in addition to insulin. This will depend on 3 things:

  • Your diabetes type.

  • How well insulin alone meets your treatment goals.

  • Other health factors.

There are different types of medicines that help treat diabetes. The goal is to control your blood sugar the best way possible, which will reduce your risk of complications. Adding other medicines may also reduce the amount of insulin you need.


People with type 1 diabetes must take insulin to stay alive. Their body does not produce it.  People with type 2 diabetes might require insulin in addition to, or instead of, other medicines. In either case, proper use of insulin is critical to control your diabetes.

There are a number of different types of insulin. Usually, you will give yourself injections, though others can be trained to give them to you. Some people have an insulin pump that delivers insulin continuously through a soft, flexible tube (canula) that is placed under the skin of the abdomen. Other sites including the hips, thighs, or upper arms may also be used.

Using insulin requires that you check your blood sugar several times a day. The exact number of times and time of day to check your blood sugar will vary depending on your type of diabetes, your type of insulin, and treatment goals. Your caregiver will direct you.

Generally, different insulins have different properties. The following is a general guide. Specifics will vary by product, and new products are introduced periodically.

  • Short-acting insulin starts working quickly (in as little as 5 minutes) and wears off in 3 to 6 hours (sometimes longer). This type of insulin works well when taken before a meal to bring your blood sugar quickly back to normal. There are several different types of short-acting insulin. Some work quickly and others last longer in your system.

  • Intermediate-acting insulin starts working in 2 hours and wears off after about 10 to 18 hours. This insulin will lower your blood sugar for a longer period of time, but will not be as effective in lowering your blood sugar right after a meal.

  • Long-acting insulin mimics the small amount of insulin that your pancreas usually produces throughout the day. You need to have some insulin present at all times, as it is crucial to the metabolism of brain cells and other cells. Long-acting insulin is meant to be used either once or twice a day. It is usually used in combination with other types of insulin, or in combination with other diabetes medicines.

Discuss the type of insulin you are taking with your caregiver or pharmacist. You will then be aware of when the insulin can be expected to peak and when it will wear off.

Your caregiver will usually have a strategy in mind when treating you with insulin. This will vary with your type of diabetes, your diabetes treatment goals, and your health history. It is important that you understand something about this strategy so you may be a partner in treating your diabetes. Here are some terms you might hear:

  • Basal insulin. You need to have a small amount of insulin present in your blood at all times. Sometimes oral medicines will be enough. For other people, and especially for people with type 1 diabetes, insulin is needed. Usually, intermediate-acting or long-acting insulin is used once or twice a day to accomplish this.

  • Prandial (meal-related) insulin. Your blood sugar will rise rapidly after a meal. Short-acting insulin can be used right before the meal to bring your blood sugar back to normal quickly. You might be instructed to adjust the amount of insulin depending on how much carbohydrate (starch) is in your meal.

  • Corrective insulin. You might be instructed to check your blood sugar at certain times of the day. You then might use a small amount of short-acting insulin to bring the blood sugar down to normal if it is elevated.

  • Tight control (also called intensive therapy). Tight control is keeping your blood sugar as close to your target as possible and keeping it from going too high after meals. People with tight control of their diabetes may have fewer long-term complications from their diabetes.

  • Glycohemoglobin (also called glyco, glycosylated hemoglobin, Hemoglobin A1c, or A1c) level. This measures how well your blood sugar has been controlled during the past 1 to 3 months. It helps your caregiver see how effective your treatment is and decide if any changes are needed. Your caregiver will discuss your target glycohemoglobin with you.

Insulin treatment requires your careful attention. Treatment plans will be different for different people. Some people do well with a simple program. Others require more complicated programs with multiple insulin injections daily. You will work with your caregiver to develop the best program for you. Regardless of your insulin treatment plan, you must also do your best on weight control, diet and food choices, exercise, blood pressure control, and cholesterol control.


Research shows that optimal treatment of your diabetes will reduce the risk of kidney, eye, and nerve complications. If you have type 1 diabetes, your risk of heart and vascular disease also decreases with good diabetes control. The better you control your blood sugars (and the lower your glycohemoglobin), the lower your risk of complications.


Although insulin treatment is important, it does have some risks. Insulin treatment may be complex, but it is critical for maintaining your good health. Frequent follow-up visits with your caregiver, at least early on, are usually needed.

  • Insulin can cause your blood sugar to go too low (hypoglycemia). This can be a dangerous complication that must be quickly recognized and treated.

  • Weight gain can occur.

  • Improper injection technique can cause hypoglycemia, skin injury or irritation, or other problems. You must learn to inject insulin properly.

  • Other medicines used for diabetes can have other complications. Discuss your medicines and their complications with your caregiver.


The goal of treating your diabetes is to allow you to live as long as you can with as few complications as possible. Several factors help you work towards this goal:

  • You should achieve a blood sugar as close to normal as possible without causing hypoglycemia. Generally, this means a glycohemoglobin of between 6% and 7%.

  • You should achieve and maintain an ideal body weight.

  • You should exercise regularly.

  • Your blood pressure should be under 130/80.

  • Your cholesterol should be controlled, with your LDL under 100. Your target may be different depending on your health factors.

  • You should not smoke.

  • You should be up to date on immunizations, including influenza and pneumonia.

  • You should be monitored for eye, kidney, heart, and vascular health regularly. Preventative medicines are sometimes used for these conditions.

Your specific goals may vary, depending on your health factors. You should discuss issues with your caregiver.


  • Do not smoke.

  • Eat a healthy diet as instructed. Ask for help if you need it.

  • Exercise regularly. Ask for help if you need it.

  • Stay up to date on your immunizations.

  • See your caregiver on a regular basis.

  • Follow your diabetes care plan carefully. Take medicines and insulin as directed. Check your blood sugar as directed, and keep track of it in a log. Understand your glycohemoglobin and other diabetes goals. Understand how to detect and treat hypoglycemia.

  • Follow your care plan for blood pressure and elevated cholesterol if you have these problems.

  • Do your blood tests as directed. This is important and helps monitor your diabetes.

  • Check your feet every night for sores or wounds.

  • See your eye doctor once a year.

  • If you have an illness that causes loss of appetite, vomiting, or diarrhea, you should speak with your caregiver about temporary changes in your insulin doses and other medicines.


  • You are having problems keeping your blood sugar at target range.

  • You are having episodes of hypoglycemia.

  • You are having side effects from your medicines.

  • You have symptoms of an illness that are not improving after 3 to 4 days.

  • You have a sore or wound that is not healing.

  • You notice a change in vision or a new problem with your vision.

  • You develop a fever of more than 100.5° F (38.1° C).


  • Your blood sugar goes below 70, especially if you have confusion, lightheadedness, or other symptoms.

  • Your blood sugar is very high (as advised by your caregiver) twice in a row.

  • An unexplained oral temperature above 102° F (38.9° C) develops.

  • You pass out.

  • You have chest pain or trouble breathing.

  • You have a sudden, severe headache.

  • You have sudden weakness in one arm or leg.

  • You have sudden difficulty speaking or swallowing.

  • You develop vomiting or diarrhea that is getting worse or not improving after 1 day.