Insulin Pumps

An insulin pump is a small, computerized device that delivers insulin continuously through a thin flexible tube (catheter) or a pod worn on the skin. Insulin pumps are used primarily for Type 1 diabetes but are also an option for Type 2 diabetes patients who require intensive insulin management.

How an Insulin Pump Works

A pump delivers insulin in two ways:

• Basal rate: A continuous, programmable low-dose infusion that provides background insulin around the clock, mimicking what a healthy pancreas delivers between meals and overnight. Multiple different basal rates can be programmed for different times of day.
• Bolus dose: On-demand insulin doses delivered for meals (based on carbohydrate content) or to correct high blood sugar. Modern pumps include bolus calculators that factor in carbohydrate intake and current glucose level.

The pump uses only rapid-acting insulin (no long-acting insulin needed), with the infusion set changed every 2–3 days.

Types of Insulin Pumps

• Traditional tubed pumps: The pump reservoir and pump body are worn on a belt/pocket with a thin tube connecting to an infusion set on the skin (e.g., Tandem t:slim X2, Medtronic 780G)
• Patch/tubeless pumps: A pod is worn directly on the skin with no tubing, controlled via a separate device or smartphone (e.g., Omnipod 5, Omnipod DASH)

Who Is a Good Candidate for a Pump?

• People with Type 1 diabetes who want tighter glucose control
• Those with frequent hypoglycemia or hypoglycemia unawareness
• People with significant dawn phenomenon (early morning glucose rise)
• Patients with variable schedules or eating patterns
• Those who find multiple daily injections burdensome
• Active individuals who want more flexibility
• Pregnant women with T1D requiring very tight glucose control

Insulin Pump + CGM = AID System

The most powerful current use of insulin pumps is in combination with a CGM to form an Automated Insulin Delivery (AID) system. The pump algorithm uses real-time CGM data to automatically adjust basal delivery, suspend insulin before predicted lows, and increase delivery when glucose is rising. The Omnipod 5, Tandem t:slim X2 with Control-IQ, and Medtronic 780G are all currently FDA-approved AID systems.

Next-Generation Closed-Loop Systems

Two highly advanced systems represent the cutting edge of automated insulin delivery:

• Twiist AID System (Sequel Med Tech): A next-generation closed-loop pump featuring a fully automated algorithm that adjusts insulin delivery based on continuous CGM data. The Twiist system is designed with a tubeless, wearable form factor and advanced predictive algorithm aimed at minimizing hypoglycemia and time-out-of-range, moving closer to a true artificial pancreas experience.
• iLet Bionic Pancreas (Beta Bionics): A uniquely autonomous closed-loop system that requires no carbohydrate counting and no basal rate programming. The user enters only their body weight — the iLet's proprietary algorithm self-learns and self-adjusts insulin dosing autonomously. FDA-approved for adults and children ≥6 years with type 1 diabetes, it represents one of the most advanced approaches to replicating the function of a biological pancreas currently available.

These next-generation systems represent a significant advancement beyond first-generation AID devices, with algorithms that are increasingly autonomous and require less manual input from the user — bringing the technology closer to a true artificial pancreas.