Back to Ask the Diabetes Team Ask the Diabetes Team
My 14 year old son has had diabetes for a little over 3 years. He takes 4 shots per day. While his Hba1c's have been good, the last two have been higher than we would like. (We would like to keep them under 7.) He has gotten in the habit of taking his shot right before he eats, rather than waiting based on his pre-meal blood reading. Neither he nor I can remember the guideline on how long to wait. I remember that he either ate right away, or waited 30 min., 45 min., or 60 min. based on his pre-meal blood reading, but cannot remember what the cutoffs were. Can you provide this information?

Puberty sure can make changes in diabetes control! Maybe it's time for your son to think of revamping his insulin program to deal with the changes that occur in adolescence: different meal times, different meals, different stresses, and lots of hormone changes, compared to way back three years ago, when he was eleven.

Your question about the timing of when it's best to give insulin depends on the type. NPH, Lente, and Ultralente (the longer-lasting cloudy insulins) are best given at about the same time each day. Sometimes, for convenience, it'll be advised that they be mixed into the same syringe as the Regular insulin (the clear, rapid-acting version of insulin).

Most diabetes professionals advise their patients to take their Regular insulin about 1/2 hour before the meal, but it's really pretty rare that a teenager (or most adults with diabetes) can give it exactly on time! In "real life," it's usually impossible to build in the ideal delay of a half-hour, and many times the time frame between the shot and the meal will necessarily be shorter.

Also, the general guideline about a half-hour does need some modification, if the blood sugar measurement at that moment is low: if the guideline were strictly followed, the half-hour between the shot and the meal would almost guarantee an episode of hypoglycemia if the blood sugar was low to start with! And, if the blood sugar is high, there's a theoretical advantage to taking the insulin more than 30 minutes before eating. So, the half-hour guideline needs to be modified, to state that if the blood sugar is below the expected levels, to eat sooner after the shot, and indeed, to eat first if the blood sugar is quite low.

One example of this guideline might be:

  • take the Regular 1/2 hour before the meal, unless the blood sugar is below 100, then eat fast;
  • if the blood sugar is below 80, eat first (then take the shot, then finish the meal).

We think that the upcoming availability of extremely-rapidly insulin analogues such as Humalog® (Insulin Lispro) will be a tremendous help to people taking insulin for diabetes: we'll be advising people to give the shot with the meal (or even after the meal!) when it's available in the U.S. to be used (it's already available in some countries).

Original posting 5 Feb 96


  Back to Ask the Diabetes Team Return to the Top of This Page

Last Updated: (none)
This Internet site provides information of a general nature and is designed for educational purposes only. If you have any concerns about your own health or the health of your child, you should always consult with a physician or other health care professional.

This site is published by T-1 Today, Inc. (d/b/a Children with Diabetes), a 501c3 not-for-profit organization, which is responsible for its contents. Our mission is to provide education and support to families living with type 1 diabetes.
By using this site, you agree to our Terms of Use, Legal Notice, and Privacy Policy.
© Children with Diabetes, Inc. 1995-2018. Comments and Feedback.