thanks friends....i am back wth my wife...and am really thank full to you for your help..
Hey there,
When my sugars start the "roller coaster effect" I feel that this is the most frustrating time of the condition. Have your wife be careful that she is not over-doing her fast acting insulin. Some times the first reaction is to fix the high as fast as possible, which for some means giving a more-than-enough dose at once. In that case I would have done my correction for the high, but perhaps skipped the carbs in dinner. Lately I've been eating no more than 5-10 carbs in a day, usually at dinner, and cutting the amount of fast acting insulin I use by a two thirds. My sugars have never been more level, no more highs after eating, severe lows way after eating, and then eating again to fix the lows. Also my energy levels have increased tremendously, and the weight loss has already taken effect. Have her try it out!
Since we don't know what your wife's insulin:carb ratios are, we have no way of knowing if 12 units of fast-acting insulin is the right amount to both correct her high and cover her carbs. With a high like that, I would tend to want to get it down first before I ate. Your wife seems to be on a roller coaster of high and low. How well educated is she in insulin dosing? If she is that high before dinner than her basal (long-acting) insulin is probably too low. She also needs to have the correct insulin:carb ratios, and know her correction factor to correct highs with fast acting insulin taking account the insulin still on board. If all of this is clear to her, and it usually works fine, then it is a freak situation and doesn't repeat.
If she has this problem frequently and isn't clear about insulin dosing as above, then she needs to get that under control. I highly recommend the book Using Insulin by John Walsh. Let me know by private message if you want the name of another website with a lot more experienced diabetics so you and she can learn from others who have been doing this for years. I'm sorry to hear she is struggling.