Now, why might we use both the intermediate-acting insulin (NPH) and the long-acting ones (detemir, glargine)?
Won't just one type or the other suffice?
Which one to use depends upon blood sugar profiles.
If your blood sugartypically rises between noon and bedtime ondays thatyou skip all your meals, you'll need glargine or detemir on arising in the morning.
We use these andnot NPH in the daytime be cause they last longer and will usually carryover until a bit past bed time.
On the other hand, we may use one or, in rare cases, two of these insulins at bedtime, to cover the overnight fasting state.
When one is needed at bedtime, we usually try the longest-acting first.
Glargine and detemir are especially valuable if the dawn phenomenon is pro longed or ifyou sleep longer than 8 hours.
Ifour initial dose ofa long- acting insulin is not adequate, we may increase it.
Sooner or later, however, we may find that late-morning blood sugars are going too low, due to the higherdose.
We might then switch over to NPH at bed time, to concentrate action during the sleep period.
One must be care ful, however, not to give too much NPH at bedtime, because large doses may cause blood sugars to drop in the middle of the night.
In practice, I prescribe intermediate-acting insulin for fewer than 1 per cent of my insulin-using patients.
There are other rare uses of NPH discussed elsewhere in this book.
WHEN DO WE USE RAPID-ACTING INSULIN?
If you're a type 1 diabetic , or a type2 diabetic who is following our diet and using oral medication and still experiencing blood sugar in creases after one or more meals , injecting regular (R), lispro (H), glulisine (G), or aspart (A) insulin prior to these meals is indicated.
By sheer coincidence, the 5-hour (assumed) minimum action time of regular corresponds approximately to the time most of us require to digest fully a mixed meal of protein and carbohydrate, and to experi ence the final effect of the meal upon blood sugars.
Regular insulin should usually be injected 45 minutes before a meal, so that it starts to work just as we start to eat.
The beta cells of some type 2s, however, mayenjoy enough of a rest from oneor twosmall doses of glargine or detemirthat theycan produce sufficient insulin to cover meals.
Since everyone is different, your insulin regimen must be custom-tailored to normalize your personal glucose
272 Treatment
profile. All this takes more effort on the partofyour physician than just theprescription ofone or two daily shots ofalong-acting insulin. Because of their very rapidaction, lispro and glulisine are also the insulins that we useto lower a highblood sugar. Since elevated blood sugars are the cause of the long-term complications of diabetes, we naturally wantto see themcome down to normal asfast aspossible. In