Insulin pens
Prefilled disposable pens or reusable pens with replaceable cartridges let users dial an exact dose and inject through a small pen needle. They're the most widely used delivery method today thanks to convenience and dosing accuracy.
Insulin pumps
A pump delivers rapid-acting insulin continuously through a small cannula placed under the skin, replacing long-acting background insulin with a programmable, adjustable trickle (the "basal rate"), plus on-demand bolus doses at meals.
Continuous glucose monitors (CGMs)
CGMs use a small sensor under the skin to track glucose levels continuously, sending readings to a phone or receiver every few minutes. They're not an insulin delivery device themselves, but are often paired with a pump.
Closed-loop / "artificial pancreas" systems
These systems connect a CGM to a pump with an algorithm that automatically adjusts background insulin delivery based on real-time glucose readings, reducing (but not eliminating) the need for manual adjustment.
Choosing between methods
The right method depends on lifestyle, insurance coverage, comfort with technology, and how much day-to-day involvement someone wants in fine-tuning doses - a conversation best had with an endocrinologist or diabetes educator.