If you are on insulin, then you should follow the guidelines that you and your doctor have established. What is your isf (insulin sensitivity factor)? This is the number of points that one unit of insulin will bring you down. You also need to take into consideration the amount of insulin on board (the amount that is still active from when you took the pre-meal shot).
Sorry I can't be more specific. If you are unsure, you need to discuss your insulin regime with your nurse educator or your doctor. Best of luck.
Dxd T1 1966, 2001 dialysis, 2002 kidney transplant, 2003 insulin pump, 2008 pancreas transplant