when is NPH insulin given
The time it takes to absorb one half of an injected dose of insulin may vary by 25 to 50 percent among individual patients. 5 For example, NPH insulin may have a duration of activity of 18 hours in one patient but an effective activity of only 9 or 10 hours in another patient.he time it takes to absorb one half of an injected dose of insulin may vary by 25 to 50 percent among individual patients. 5 For example, NPH insulin may have a duration of activity of 18 hours in one patient but an effective activity of only 9 or 10 hours in another patient.