It starts working about 15 minutes after injection, peaks (or is at maximum effectiveness) in about 1 hour, and continues to work for 2 to 4 hours after injection.
Examples: Aspart (Fiasp, NovoLog), glulisine (Apidra), lispro (Admelog, Humalog)
Regular or Short-Acting
It starts working 30 minutes after injection, peaks anywhere from 2 to 3 hours after injection, and continues to work for about 3 to 6 hours.
Example: Humulin R, Novolin R
It starts working 2 to 4 hours after injection, peaks about 4 to 12 hours later, and lasts approximately 12 to 18 hours.
Example: Humulin N, Novolin N
It is most often combined with rapid- or short-acting insulin. It starts working several hours after injection and tends to lower glucose levels up to 24 hours or almost a full day.
Examples: Lantus, Levemir, Basaglar
It starts working in 6 hours, but it does not peak and lasts about 36 hours, and in some cases longer than that.
Examples: Tresiba, Toujeo
It starts working in 12-15 minutes and lasts about 3 hours.
How is it Administered?
Injections are needed multiple times throughout the day, though frequency varies on a case-by-case basis and typically involves a combination of both rapid- or short-acting paired with a long-acting one. Injections are typically administered to the thigh, buttocks, abdomen, or upper arms. Learn more about insulin injection techniques.
Pumps deliver insulin throughout the day (basal) and large amounts (bolus) to cover meals or correct high-glucose levels. Most people use rapid-acting in their pumps. Pumps are often worn on the hip and can be detached from the infusion site (where the temporary needle or tube enters the body). Sites are typically in the upper thigh, abdomen, or along the tricep.
In 2016, the FDA approved the first largely automated insulin dosing system known as an artificial pancreas system. It is a hybrid closed-loop system that requires minimal user intervention. Artificial pancreas systems combine the technology of a pump with that of a continuous glucose monitor (CGM). This pump/CGM combination is typically connected to the body in the same locations as a standalone pump.
Side Effects of Long-Term Use
There are a few direct side effects. When dosing is off or carbohydrate intake is miscalculated, people with T1D may experience hypo- or hyperglycemic episodes. These states may result in headaches or flu-like symptoms. People with T1D may also experience itching, loss of fat at the injection site, pain, and rash or redness at injection or pump/CGM sites.