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Quick Facts

Drug Treatment of Diabetes


The Manual's Editorial Staff

Last full review/revision May 2021| Content last modified May 2021
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Diabetes is a lifelong disease in which your blood sugar (glucose) levels are too high.

Why do people with diabetes need drugs?

If your blood sugar stays high for a long time, you will have serious complications of diabetes. If watching your diet and getting regular exercise don't keep your blood sugar under control, you'll need to take medicine. The medicine doctors prescribe depends on what type of diabetes you have and how high your blood sugar is.

Sometimes, diabetes medicines make your blood sugar level too low. Low blood sugar is called hypoglycemia.

What is insulin?

Insulin is a natural hormone your body makes that lowers your blood sugar level. Insulin also comes as a medicine that you can take. Most people who need to take insulin do so by injection (shots). A new form of insulin can be taken through an inhaler.

Do I have to take insulin?

If you have type 1 diabetes, you have to take insulin. In type 1 diabetes, your body doesn't make any insulin.

If you have type 2 diabetes, you probably won't have to take insulin unless other medicines don't control your blood sugar well enough.

What types of insulin can I use?

Insulin comes in different forms based on how quickly it starts working and how long it lasts:

  • Rapid-acting insulin starts working in 5 to 15 minutes and lasts about 4 hours—you may inject rapid-acting insulin right before you eat

  • Regular insulin starts working in 30 to 60 minutes and lasts 6 to 8 hours

  • Intermediate-acting insulin starts working in 1 to 2 hours and lasts about a day

  • Long-acting insulin has very little effect in the first few hours but lasts 20 to 36 hours

You may take more than one type of insulin. And you may take insulin once or several times a day. What type you use and how often you take it depends on several things, including:

  • How sensitive your blood sugar levels are to changes in diet and activity

  • How often you're willing to test your blood sugar level

  • How often you're willing to take insulin

  • How well you can stick to your diet and exercise routine

Doctors will figure out which type of insulin will work best for you. Some people take the same amount of insulin every day. Other people change how much insulin they take every day depending on their diet, exercise, and blood sugar level. Your insulin needs may change if you gain or lose weight, change how much exercise you do, have a lot of emotional stress, or get a sickness or infection.

How do I take insulin?

Most often, you'll take insulin as an injection (shot) under your skin. There are different ways to take insulin injections:

  • An insulin syringe that you fill from a bottle of insulin

  • An insulin pen (a device that holds several doses of insulin)—the pen has a dial that you turn to adjust the insulin dose and a button you push to inject the insulin

  • An insulin pump (a battery powered device that pumps insulin through a small needle left under your skin)

Less common ways you might take insulin include:

  • An inhaler device that lets you breathe in the insulin

  • An air pump device that blows the insulin under your skin

What problems can insulin cause?

If you're taking too much insulin or not eating regularly, your blood sugar can go too low (hypoglycemia).

Over time, your body may get resistant to insulin. This means that your body may need more and more insulin to get the same result.

Also, the place where you give yourself the shot may have problems, such as:

  • Allergic reaction, causing pain, burning, redness, itchiness, and swelling

  • Fat deposits, making your skin look lumpy

  • Dents in your skin

You can avoid most of these problems by giving yourself shots in different places on your body.

What other medicines are used to treat diabetes?

Besides insulin, several other types of medicines are used to control blood sugar in people with diabetes. Some are taken by mouth and others as a shot. Sometimes you need more than one medicine or need to take insulin along with these medicines. Doctors choose the right medicines for your diabetes so that your blood sugar is under control without causing it to go too low.

Diabetes medicines work in different ways to control your blood sugar, including:

  • Stimulating your pancreas (the organ in the belly where insulin is made) to put out more of your body's own insulin

  • Keeping the liver from releasing sugar into your bloodstream

  • Keeping your stomach and intestines from letting the sugar in foods get into your bloodstream

Diabetes medicines can cause hypoglycemia and other side effects. Talk to your doctor to know what to look for.

When taking insulin or other diabetes medicines, it's important to check your blood sugar often and see your doctor to:

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