An adult client’s insulin dosage is 10 units of regular insulin and 15 units of NPH insulin in the morning. The client should be taught to expect the first insulin peak:
A. As soon as food is ingested.
B. In two to four hours.
C. In six hours.
D. In ten to twelve hours.
Correct Answer: B. In two to four hours.
The first insulin peak will occur two to four hours after administration of regular insulin. Regular insulin is classified as rapid-acting and will peak two to four hours after administration. The second peak will be eight to twelve hours after the administration of NPH insulin. This is why a snack must be eaten mid-morning and also three to four hours after the evening meal.
Option A: Rapid Acting Insulin Analogs (Insulin Aspart, Insulin Lyspro, Insulin Glulisine) has an onset of action of 5 to 15 minutes, peak effect in 1 to 2 hours, and duration of action that lasts 4-6 hours. With all doses, large and small, the onset of action and the time to peak effect is similar, The duration of insulin action is, however, affected by the dose – so a few units may last 4 hours or less, while 25 or 30 units may last 5 to 6 hours. As a general rule, assume that these insulins have a duration of action of 4 hours.
Option C: Regular Human Insulin has an onset of action of 1/2 hour to 1 hour, peak effect in 2 to 4 hours, and duration of action of 6 to 8 hours. The larger the dose of regular the faster the onset of action, but the longer the time to peak effect and the longer the duration of the effect.
Option D: Long-acting insulin analogs (Insulin Glargine, Insulin Detemir) have an onset of insulin effect in 1 1/2-2 hours. The insulin effect plateaus over the next few hours and is followed by a relatively flat duration of action that lasts 12-24 hours for insulin detemir and 24 hours for insulin glargine.