Types of insulin available include rapid-acting, short-acting, intermediate-acting, long-acting, and pre-mixed. This graph shows the approximate action on insulin levels of several insulin medications. The bolus, or quick-acting insulin is given at mealtimes and offsets the effects of dietary carbohydrates. The basal or longer-acting insulins offset hepatic glucose secretion, meeting the body’s basic metabolic energy needs. Rapid-acting works has an onset of 10-30 minutes and peaks between 30-90 minutes. Variations are seen in duration from 1-2.5 or 3-5 hours. Short-acting, shown here as “regular”, have and onset of ½ to 1 hour, a peak of between 2-5 hours, and varied durations from 2-3 hours or 5-8 hours. Intermediate-acting insulin, such as NPH or Lente, have onsets between 1-2.5 hours, a peak between 3-12 hours, and a duration of 18-24 hours. Long-acting includes ultralente, lantus, and levemir or detemir. The onset ranges from ½ to 2 hours, peak levels are varied from 6-8 hours or 10-20 hours, except for lantus, which is delivered at a steady level. The duration ranges from 20-36 hours. This type of insulin is often combined with rapid or short-acting insulin therapy. Pre-mixed include products such as humulin, novolin, novolog, and humalog. These mixes have both a quick onset and a long duration.

It is important to understand the complementary action of basal and bolus insulin.

Basal or long-acting insulin:

Offsets hepatic glucose secretion,

Meets the body’s basic metabolic energy needs, and

Necessary levels vary; usually providing ~40-50% of daily insulin total.

Bolus or mealtime rapid-acting insulin:

Offsets effects of dietary carbohydrates,

Provides a significant peak action at 1 hour post-meal, and

The use of Insulin:Carb ratios allows flexible meal planning for this type of treatment.

Treatment Options: Insulin Delivery Devices

Insulin syringes have varying needle length and are generally quite thin and virtually painless. Insulin pens are considered faster and easier than syringes, and are convenient, provide accurate dosing, and use very thin disposable needles.

Insulin is delivered subcutaneously using a variety of injection sites, which may include the abdomen, sides (love handles), thighs, buttocks, and arms. It is suggested that a variety of spots should be used at each site. Pinching and cleansing is not generally necessary. A few seconds should be allowed for full delivery.

Insulin pumps are external, but connected to an indwelling subcutaneous catheter to provide rapid-acting insulin at programmable basal rates. It eliminates extra injections, has a dose calculator function, and provides a bolus history. Pumps require the support of qualified professionals.

There are also injection ports that can allow a single injection site to be used for several days before replacement.