Q: Recently I read an article in Post Graduate Medicine (“Effective Insulin Use,” Vol. 95, No. 8, June 1994, pgs. 52, 54, 58-60, 63-64, and 67). The article suggests the patient not eat if the blood glucose is greater than 150 mg/dl. I would appreciate you reading this article and giving me your opinion.
Donna Doty, RN, BSN, CDE
[Editor: An excellent question. We encourage all our readers to send us questions to answer. Coincidentally, the article you ask about was written by one of DIABETES IN-TERVEIW’s advisory board members: Nancy Bohannon, MD. We submitted your question to our board member Peter Lodewick, MD, diabetes expert and author of A Doctor Looks at Diabetes: His and Yours. Before we print his answer to your question, we’re presenting an excerpt from Dr. Bohannon’s article.]
“My routine advice is as follows: if the blood glucose value is over 150 mg/dl before a meal, insulin should be taken and the meal postponed (not skipped) until the blood glucose is below 150 mg/dl. The glucose level should be checked hourly until it is below 200 mg/dl and then every 1/2 hour until it is below 150 mg/dl. A level that is still high after 1 1/2 to 2 hours without the patient’s eating is an indication that it was a good thing the patient didn’t eat! In the past, most patients would have eaten, saying, ‘my doctor told me never to miss or be late for a meal because I could get hypoglycemia.’ However, if the insulin was taken 3 hours previously and the blood glucose level remained above 150 mg/dl, food obviously was not necessary.
“What happens if the blood glucose level is still high after 2 to 3 hours? A few more units of insulin should be taken and the meal again postponed until the glucose level is below 150 mg/dl. Occasionally, a patient in really poor control goes for 8 hours or more without eating because glucose levels remain consistently high despite extra insulin every 3 hours. Again, that verifies that eating would have been inappropriate and usually indicates a need for a total revamping of the insulin regimen.
“When I tell patients ‘don’t eat,’ I mean they are not to eat a significant amount of carbohydrate (no more than 10 g total). To appease hunger while waiting for glucose levels to become acceptable, the patient can consume large amounts of raw lettuce, celery, cucumbers, jicama, and similar foods (with or without a vinegar dressing); gelatin, sodas, and Popsicles (all sugar-free); dill pickles; and other ‘free foods.'”
A: In response to Ms. Doty’s question, I read the article and agree very much, if not in total, with what Dr. Bohannon (the article’s author) has to say-although I can understand the confusion that many may have without further clarification. I believe Dr. Bohannon’s point is that if someone eats, especially any significant amount of carbohydrate, when their blood sugars are already 150 mg/dl, it will result in a rapid rise (in some patients over 400 mg/dl) in blood sugar. Blood sugars that high represent a lack of insulin, and eating carbohydrates will only put more sugar in the system. It is therefore better to wait for the blood sugar to go below 150 mg before eating-this may occur if the insulin is given at least 45 minutes before eating. Once this occurs then eating will be all right-again as long as it’s not too much.
In some instances, when pre-meal blood sugars are over 300, skipping the meal in part and/or possibly giving a small amount of extra insulin may help bring the blood sugar down-at which point the part of the meal that was skipped could be eaten later. All of this should be reviewed with a patient’s physician and/or health care team before making any specific recommendations for an individual patient. As you know, that’s why diabetes can be such a balancing act. People with diabetes can be smart in doing this.
Dr. Peter Lodewick, MD
Diabetes Care Center Birmingham, AL