When my blood sugar goes over 300 I have to frequently urinate, about every 10 to 15 minutes, and also I feel bloated. My vision can become impaired; blurred, and I might even feel faint. Hyperglycemia can also cause dehydration. I have noticed that the pain in my feet and lower legs increases with high blood sugar levels, and all of these symptoms are usually relieved when my blood sugar is normalized.
I have been a type 2 for about 10 years; had a sudden onset of adult diabetes right before my 50th birthday. I was getting up every 10 to 15 minutes to go to the bathroom, all night long, and allot of the other symptoms described above. On my way to work I stopped at a hospital emergency room and told them that I didn’t feel good. They ran some tests on me and told me that my blood sugar level was 900. I was admitted to the hospital. Since then my blood sugar has seldom gone over 400. There has been a few times where I have been 300 or better, but my most recent A1c was 6.8, and I’m trying to bring it down even lower. In my opinion some of the most damaging effects of short term high blood sugar levels are that they add to the damaging long term effects, but I do agree that it is a very individual thing. When I first was diagnosed with diabetes the doctor told me that I was very fortunate because some people die, go into a diabetic coma, or experience severe diabetic ketoacidosis, with a blood sugar level of 700; so my blood sugar being at 900 was very critical.