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From Vidalia. Louisiana, USA:

My eight year old daughter was diagnosed with type 1 diabetes about seven months ago, is on twice daily NPH and Humalog, and since then her blood sugar levels have been up and down (anywhere from 40-320 mg/dl [2.2-17.8 mmol/L]). I have noticed that if I check it about an hour after she eats it can be as high as 250 mg/dl [13.9 mmol/L]. Am I checking too soon after eating (because it goes right back down)? Is that unusual to go that high if we are sticking to her diet? Also when she wakes up her blood sugar is fine, but, bout three to four hours after she gets her insulin, her level is about 300 mg/dl [16.7 mmol/L], and she is usually is low (about 50 mg/dl [2.8 mmol/L]) in the evening before bed. What do you think is going on with her?


In order to best answer your question for you, you have to remember what you were taught about insulin actions (during those first frantic days when your daughter was diagnosed). NPH insulin has an onset of action a couple of hours after it is given and has its maximal effect ("peak effect") about six to eight hours later. Therefore, the morning dose of NPH has its greatest influence on the suppertime glucose reading. The evening NPH dose has its greatest influence on the glucose reading the following morning.

Humalog insulin has an onset of action within minutes (perhaps as fast as five minutes) with its peak effect in about 90 minutes to two hours. So, it does not surprise me that three to four hours after a meal, you note that the glucose readings are very high. Regular insulin works within 30 minutes after a dose and has its peak effect about three to four hours later.

Checking the value one hour after a meal may be a little too soon, but if the value two hours after a meal with which you have given Humalog is significantly high, then that suggests that the dose of insulin (relative to the food consumed) is too low. That is why many people who prescribe Humalog advocate that families learn carb counting and dose the Humalog accordingly. If you dose Humalog optimally, the glucose level after meal should be reasonably similar to the glucose level before the meal. There is more emphasis these days about keeping the after-meal (postprandial) glucose levels in tighter ranges.


Original posting 13 Sep 2001
Posted to Daily Care


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Last Updated: Tuesday April 06, 2010 15:09:26
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