Cathy, I responded to your post and then your post disappeared and only my reply remained, so it appeared I was talking to a wall!! I'm copying my reply and I hope you come back!
This is in response to your questions about the Glyburide not working:
The branflakes will keep your blood sugar high. It doesn't matter if you use artificial sweetener or not. And low fat milk (if you use that) has more carbs than 2% or whole milk. I don't know which kind of milk you're using.
Your fasting and the other blood sugar readings are very high and over a period of time, they can cause health problems like neuropathy (which you already have), glaucoma or other eyesight problems leading to blindness, circulation problems especially in the limbs, heart and kidney problems.
Diabetes meds should be able to control your blood sugar and keep it at more normal levels to avoid these health complications. If the Glyburide can't do this, your doctor should change it to another or a combination. Or, maybe you should be on insulin and another drug. In short, your medication needs to be re-evaluated before you have more health problems caused by this very high blood sugar.
In my opinion: you should probably change doctors. I think this has been going on for quite awhile, since you started posting here. In all this time, your blood sugar has been at critical levels and this is unacceptable!
Diet and some kind of exercise helps medication do its job. If you're eating bran flakes for breakfast, your blood sugar will rise. If your fasting blood sugar is already critically high and you eat bran flakes for breakfast, your blood sugar will go even higher, so it seems like your diet is working against the Glyburide.
Cathy, I don't know if the high pressure in your head is the high blood sugar. Maybe it is. Could it also be high blood pressure? Can you measure that at home? Do you have a cuff?
Do you have any sort of regular, sustained exercise that you do daily?