Insulin Therapy for Controlling Type 1 Diabetes

People with type 1 diabetes must take insulin, but there are choices about how to administer it.

Medically reviewed by Farrokh Sohrabi, MD

People with type 1 diabetes must take insulin to manage their blood sugar levels. This is because the pancreas, the organ in the body that normally produces insulin in response to changing blood sugar levels, does not work correctly.

Diabetes: What Is Insulin?

Insulin is a hormone that helps the cells in your body use the energy in blood glucose, also called blood sugar. It is made by the pancreas on an as-needed basis.

Type 1 diabetes occurs when your pancreas cannot make enough insulin to control blood sugar levels. Out-of-control blood sugar levels can be very damaging to your health, which is why people with type 1 diabetes must take insulin every day to keep blood sugar levels regulated.

Diabetes: Types of Insulin

If you have type 1 diabetes, you will probably take different types of insulin. The exact combination may change throughout your life, but will usually include:

  • Long-acting insulin provides a background level of insulin throughout the day.
  • Rapid-acting insulin takes effect within 15 minutes and lasts up to five hours.
  • Short-acting insulin starts working within 30 minutes and lasts up to eight hours.
  • Intermediate-acting insulin takes effect within three hours and lasts up to 16 hours.
  • Pre-mixed insulin is usually a combination of rapid-acting and intermediate acting insulin that will last for about 16 hours.

Diabetes: Find the Right Insulin Mix

As you continue to monitor your blood sugar levels throughout the day, your doctor and diabetes team will help you decide which kinds of insulin you need to take at what time.

“There are several different methods of creating a regimen. For people with type 1 diabetes, we generally try to create a regimen that would approximate what the pancreas would do if it was functioning accurately,” explains Suzanne Ghiloni, RN, BSN, a diabetes educator at the Joslin Diabetes Center in Boston. “We will use a long-acting insulin to provide a baseline and would supplement with a rapid or fast-acting insulin. These are used to cover food intake and to correct high blood glucose.”

People who do not want to give themselves multiple shots might choose a premixed option, says Ghiloni. “With premixed insulins, they have a set combination. People may take two shots a day, which simplifies it, and it would be a fixed dose. The problem with that is that it can’t be individualized. When you are on premixed insulin with rapid and intermediate insulin, if you raise one, you have to raise them both.”

Diabetes: Insulin Delivery Methods

Insulin is usually injected into your body. You have various options for insulin delivery:

  • Syringe. This is the traditional needle-and-vial shot method that you or someone in your family will give you several times a day. Two things to keep in mind: Syringes are made to match with the dose, so make sure you buy the right syringe. And different syringes measure differently, so be careful if you switch syringe types.
  • Pen. A pen does the same work as a needle and vial, but it may be more appealing to some people with type 1 diabetes because you can dial your dose more quickly and easily. “The pens are more portable and, in many cases, much more discrete. They look less medicinal,” says Ghiloni. Some pens come prefilled and are tossed when done; others have cartridges that can be removed and replaced. Which type works best for you depends primarily on the dose you need.
  • Jet injectors. These are similar to pens, but do not have a needle. Instead, a very high-pressure, tiny blast of air forces insulin through the barrier of your skin. Your doctor or nurse may have to teach you how to use this correctly.
  • Pump. A pump, which looks like a beeper or small cell phone, is often worn clipped to your belt or clothing. Doses of insulin are delivered throughout the day through tubing that connects the pump to a catheter that you insert just under your skin. Pumps can be programmed and adjusted. Says Ghiloni, “There’s a lot of creativity that can be [put to use when] using an insulin pump.” However, people who are not good at responding to the changes in their blood sugar levels wouldn’t be good candidates for a pump until they learn better troubleshooting skills, she warns.
  • Injection port. This is a thin tube, or cannula, placed just under your skin and held in place with an adhesive patch. You then inject insulin through the port instead of having to inject at various sites on your body each day. The port is replaced after several days.

With creativity and monitoring, patients with type 1 diabetes can find an insulin delivery plan that works for their lifestyle.

Last Updated: 05/07/2014