Insulin Pump: What It Is, How It Works & Types (2025)

What is an insulin pump?

An insulin pump is a wearable medical device that supplies a continuous flow of rapid-acting insulin underneath your skin. Most pumps are small, computerized devices that are roughly the size of a juice box or a deck of cards.

Insulin pumps are an alternative to multiple daily injection (MDI) insulin therapy (syringe or pen injections) for people with diabetes who require insulin to manage the condition.

The technology for insulin pumps is rapidly evolving. All pumps available in the United States today integrate with CGM (continuous glucose monitoring) technology and offer the ability to automatically adjust your insulin needs based on your current glucose levels.

Advertisement

Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy

How does an insulin pump work?

An insulin pump mimics how your pancreas would naturally release insulin. It delivers insulin in one of two ways:

  • Small and continuous insulin doses: This is called basal insulin. You’ll likely have multiple basal rates in certain hour increments throughout the day. This is because your body requires different amounts of background insulin throughout a 24-hour period. For example, most people tend to require more background insulin in the morning hours than the evening hours due to natural morning surges in cortisol, which raises your blood sugar. You’ll need to change these basal rates over time as your body and routines change. You’ll work with your healthcare provider to adjust them as needed. All pumps have the ability to automatically adjust basal doses based on your glucose levels from a connected CGM. Most pumps also have a manual setting that allows the pump to deliver basal rates programmed by the user and their healthcare provider.
  • Manual surges of insulin when eating and to correct high blood sugar: This is called a bolus. The pump uses the information you enter about your carbohydrate intake and blood sugar level to calculate how much bolus insulin you need. Most pumps recommend a dose to you, which you then confirm or adjust before they deliver the insulin.

Each type and brand of pump has various settings and technology. Examples include:

  • Integration with CGM technology to automatically increase, decrease or stop insulin release based on your glucose level.
  • Options to manually increase or decrease your basal rate for a certain amount of time.
  • Alarms to alert you of a low battery or low reservoir, for example.
  • Alarms to alert you if your glucose level is out of range if your CGM communicates with your pump.
  • Connectivity to phone apps and other smart devices.

Types of insulin pumps

There are two main types of insulin pumps: those with tubing and those without tubing.

Tubed insulin pumps

As its name suggests, a tubed (tethered) insulin pump has a long, thin tube that connects the pump itself to a cannula under your skin to deliver insulin. Parts of a tubed insulin pump include:

  • The pump machine and technology: The pump is made of durable plastic and metal. It has a screen for viewing and selecting different settings and data. Along with the pump technology, it contains a cartridge (reservoir) of insulin. It may have a replaceable or rechargeable battery depending on the brand. The maximum amount of insulin a reservoir can hold varies based on the pump type. But you fill it up based on how much insulin you typically need over two to three days. You can keep the pump in a pocket or clip it to your pants or other clothing items.
  • The tubing and infusion set: The tubing (which is several inches long) connects the reservoir of insulin in the pump to an infusion set on your skin. The infusion set sticks to your skin with adhesive and has a smaller, flexible plastic tube (cannula) that goes underneath your skin. The cannula is a few millimeters long. You insert the infusion site manually or with an injecting device. The set has a needle that runs through the cannula so it can pierce your skin during insertion. You then remove the needle so only the cannula remains. You can insert the infusion set on your upper arm, belly, hip, buttock or thigh.

You should change most reservoirs and infusion sets every two to three days. You must change your reservoir if it runs out of insulin. You use new infusion sets, reservoirs and tubing every time. But the pump itself typically lasts for multiple years.

While some tubed insulin pumps are waterproof, people typically disconnect them from the infusion site when they take a shower, bathe or swim. You can then reconnect the pump and tubing to the infusion site afterward. Some tubed pumps are just water resistant, not waterproof.

Tubeless insulin pump

Tubeless insulin pumps (patch pumps) also use a flexible plastic tube (cannula) under your skin. But the insulin reservoir and the cannula are part of one “pod” that sits on your skin with an adhesive patch. There’s no external tubing. You then operate the pump wirelessly with a handheld controller.

You use each pump — or pod — one time. Like a tubed pump, you change it every two to three days and must change it if the reservoir runs out of insulin.

Before attaching the pod, you fill the reservoir with insulin and attach the adhesive to your skin. You then push a button that releases a needle that’s threaded through the cannula in the pod. The needle retracts back into the pod, and the cannula remains under your skin. You can wear the pump on your upper arm, belly, hip, buttock or thigh.

Tubeless insulin pumps are waterproof, so you can bathe and swim with them on.

Brands of insulin pumps

Brands of insulin pumps currently on the market in the United States include:

  • iLet® Bionic Pancreas System (tubed pump).
  • Medtronic MiniMed™ (multiple tubed pumps).
  • Omnipod® (multiple tubeless pumps).
  • Tandem® t:slim (multiple tubed pumps).

Another tubeless pump, the Accu-Chek® Solo Micropump System, is only available in the United Kingdom but is awaiting U.S. FDA approval.

Who uses insulin pumps?

Anybody with diabetes who requires synthetic insulin may use an insulin pump. This includes people with Type 1 diabetes — both children and adults — and some people with Type 2 diabetes. People with Type 3c diabetes or monogenic diabetes may use a pump, as well.

Each insulin pump has different Food and Drug Administration (FDA) approvals regarding how old you can be to use it. Some insulin pumps have approval for children as young as 2. Most other pumps have approval for people 7 years and older.

Insulin pumps are one insulin therapy option for diabetes management — they’re a personal choice. You may want to use an insulin pump if you (or your child):

  • Find it challenging to reach your target blood sugar range with multiple daily injections (MDI).
  • Want more flexibility and precision in dosing insulin.
  • Have unpredictable schedules and/or eating habits.
  • Require small doses of insulin. This typically applies to toddlers and children with diabetes.
  • Have gastroparesis (experience delays in food absorption).
  • Experience dawn phenomenon.
  • Are preparing for pregnancy.

Who shouldn’t use an insulin pump?

Insulin pumps aren’t the best option for everyone — for a variety of reasons. Some things that may not make you or your child an ideal candidate for an insulin pump include:

  • Issues with manual dexterity: You’ll need to use your hands and fingers to load or fill an insulin reservoir and press buttons on the pump. If you have poor dexterity, like from hand arthritis or neuropathy, it may be challenging to use a pump.
  • Blindness and low vision: If you have blindness or low vision, you may have limited options with pump technology. You’ll need to consider the available pump features, like screen size, screen contrast, letter and number size and backlighting.
  • Issues keeping the pump attached: If you or your child has sensory challenges, for example, or severe skin allergies, a pump may not be best since it must be attached to you at almost all times.
Insulin Pump: What It Is, How It Works & Types (2025)

References

Top Articles
Latest Posts
Recommended Articles
Article information

Author: Van Hayes

Last Updated:

Views: 6222

Rating: 4.6 / 5 (66 voted)

Reviews: 89% of readers found this page helpful

Author information

Name: Van Hayes

Birthday: 1994-06-07

Address: 2004 Kling Rapid, New Destiny, MT 64658-2367

Phone: +512425013758

Job: National Farming Director

Hobby: Reading, Polo, Genealogy, amateur radio, Scouting, Stand-up comedy, Cryptography

Introduction: My name is Van Hayes, I am a thankful, friendly, smiling, calm, powerful, fine, enthusiastic person who loves writing and wants to share my knowledge and understanding with you.