The client's fasting blood glucose level is 215 mg/dL at lunch time. Per the sliding scale, the nurse administers 4 units of lispro insulin subcutaneously at 1130. What time is the client most at risk for hypoglycemia?

A. 145: This time is too early for the onset of action to peak. Lispro insulin typically begins lowering blood glucose within 15 minutes, but hypoglycemia risk is highest at its peak, not at onset. B. 1230: Lispro is a rapid-acting insulin with a peak effect occurring 30–90 minutes after injection. Since it was administered at 1130, the client is most at risk for hypoglycemia around 1230 when the insulin effect is strongest. C. 1530: By this time, the effect of lispro is declining since its duration is about 3–4 hours. The highest risk window for hypoglycemia has already passed. D. 1830: This is well beyond the duration of action for lispro insulin. Hypoglycemia from this dose would not be expected this late unless additional contributing factors, such as delayed meals or excessive activity, were present.