Rise in b.suger

i take short acting humiinsulin r at morning then after 30 minute i take break fast then i go to school where i take small snake in lunch break around 10.30 am when i could not take that with in 3 to 4 hour of humiinsulin and i take this snake in between 5to 6 hour after early morning insuling the next b.suger came aroud 250 to 300 suger why is it so why when i take food from 5to 7 hour after humiinsulin next b.suger came 250 or above when i take this with in 3 to 4 hour of humiinsulin next suger came around 150 i also take basal levamir insulin at evening 6 pm

Hello Shivika,

As I understand it, Huminsulin R peaks between 2-4 hours after injection. So any snack you have around 3-4 hours after injection will be mostly covered by that injection and your blood glucose won’t rise too high. If you have a snack 5-6 hours after injection, the majority of the insulin will have already been used by your body, so there will be less active insulin in your body to counteract the additional carbs from the late snack.

Some technical details on huminsulin r, including a graph of how long it stays active post-injection, can be found in this technical paper.

Best wishes, Mike