When most of us non-diabetics think of diabetes medication, we have no idea that it comes in many different forms. Here is an overview of the different types and how they might be used for an insulin dependent diabetic:
- Long acting or “basal” insulins–Glargine (Lantus™) Levemir (Detemir™), one of these is typically given once a day to provide a steady amount of insulin for 20 to 24 hours. This mimics what your pancreas puts out when you are not eating. One of these are used in addition to a short or rapid acting insulin that is taken with meals.
- Intermediate insulin–NPH, this is typically given twice a day, usually along with a short or rapid acting insulin. The effect of NPH starts in 2 to 4 hours and is greatest 4 to 10 hours after it is given; its effects last for 10 to 16 hours.
- Short acting insulin– “regular” insulin– it’s effect starts in 30-60 minutes and is greatest in 2 to 3 hours after it is given; it lasts for 5 to 8 hours. This is commonly prescribed twice per day in a combination with NPH; the diabetic may “draw up” a certain amount of each insulin or be given a pre-mixed “insulin pen”–the pen might contain 70% NPH and 30% Regular, or 50% NPH and 50% Regular.
- Rapid acting insulin–Aspart (Novolog ™), Lispro (Humalog™) or Apidra (Glulisine™)–these are typically given right before a meal. They start working within 5 to 15 minutes, and have their greatest effect 30 to 90 minutes after they are given; they last less than 5 hours. Rapid acting insulin is sometimes given twice a day in a mixture with NPH. Pens are available in 50 to 75% NPH and 25-50% rapid acting insulin.
The type prescribed depends on a person’s lifestyle. If you have the same mealtime schedule, and eat similar foods each day, you could be a candidate for a two shot per day regimen containing NPH and either short or rapid acting insulin. If you never know when or how much you will eat, you need a more flexible insulin schedule. You might given one of the long acting insulins once a day, and then a rapid acting insulin right before meals–you can adjust the amount of rapid acting insulin depending on what your pre-meal blood glucose is and the amount of carbohydrate you are going to eat.
Diabetes medication: What about an insulin pump?
An insulin pump uses just rapid acting insulin. The pump is programed to give a certain amount of insulin every hour to mimic the basal insulin produced by a working pancreas. The pump wearer checks her blood glucose, calculates the amount of carbohydrate she will eat at a meal or snack, and then tells the pump to give the appropriate amount of insulin to “cover” the meal or snack. A pump is fantastic for the active person, as it can be adjusted for a variety of situations. This takes a lot of training for the diabetic individual, but many people find it the best way to control their blood glucose levels.
This is a very brief explanation of insulin, but I hope it helps you to understand why you or your loved one is given a specific prescription. Next week, I will give an overview of oral diabetes medications. In future posts, I will discuss how insulin and oral medicines are dosed, side effects, and how to eat to keep blood glucose under control.