High blood sugar occurs primarily in people who suffer from diabetes. In most people, the insulin produced by the pancreas balances the glucose sugar levels in the bloodstream. When there is not enough insulin or it is ineffective, there is too much glucose circulating. This condition is called hyperglycemia. The Mayo Clinic explains that this can occur if you ingest too much glucose or if your diabetes medication is not properly regulating your system. Illnesses and some medications also may produce hyperglycemia.
Frequent Urination and Fatigue
Too much glucose in your body cannot be used by your system, so it flushes it out through urination. If your blood sugar is high, you may find you must make frequent trips to the bathroom to urinate, the Mayo Clinic reports. This typically is accompanied by greatly increased thirst. Whatever you drink, however, will be flushed away, so your thirstiness will be continual. This constant flushing of liquid along with the lack of nutrients being absorbed into your body because of high blood sugar also can make you feel weak and fatigued.
Headaches and Blurry Vision
Hyperglycemia may induce headaches because it is unbalancing your body systems. These types of headaches often persist or return. The same imbalance can affect your eyesight. This happens because too much fluid is being ejected from your body via urination. Your eyeballs need a certain level of fluid inside them in order to allow you to focus your eyesight effectively. When these levels are diminished, your vision may become blurry.
Nausea
If you do nothing to help rectify your high blood sugar levels--such as taking medicine, dieting and exercising--hyperglycemia can become serious. If you have had prolonged elevated glucose levels, you may become nauseous and you may vomit. You may experience pain in your abdomen, and there may be a fruit-like odor to your breath.
Confusion and Coma
Prolonged hyperglycemia can have serious consequences. It may affect your mental capacity, making you confused about time, day and date, or it may make it difficult for you to follow conversations. In very severe cases of high blood sugar levels, you may slip into a coma.
Breathing Problems and Toxins
Very high levels of glucose in your body for an extended period also may make you short of breath, feeling as if you cannot breathe properly. You also may build up ketones, or toxic acids, in your urine and blood. According to the American Diabetes Association, this problem cannot be rectified with exercise because ketones may elevate your glucose levels.
