Why do anti-diabetic oral medications quit working?

I am a nursing major and am finishing up a final project about type 2 diabetes mellitus, I have one more question and I am stumped! I have looked all over the internet and haven't found a direct answer. So can any one help me? I need to know why oral meds for diabetes lose their effectiveness. (Not speaking about insulin btw, just oral medications.)

Written By Nurse007

{ 1 comment… add one }
  • lasmal January 22, 2009, 1:56 am

    The only thing I can think of is that some oral anti-diabetics, like glipizide, work by causing the functioning beta cells in the pancreas to release insulin, which leads to a decrease in blood glucose. Over time, even people with well controlled DM 2 experience a deterioration of beta cells, decreasing the effectiveness of the medication