When blood sugar levels exceed 150 to 200 milligrams per deciliter of blood, dehydration, excessive urination and other symptoms of illness begin to occur, according to Aetna InteliHealth. High blood sugar can lead to a weakened immune system, weakness and fatigue. It can also encourage the growth of bacteria.
As blood sugar levels rise, excess sugar is pumped into the kidneys, taking fluids with it, states Aetna InteliHealth. As a result, the kidneys produce more urine than normal, leading to dehydration. In severe cases, this may require intravenous intervention. The loss of this sugar also results in weight loss and appetite increase. High blood sugar levels can affect the water content of the body in an unusual manner. Water starts soaking into tissues or leaking out of others, preventing normal or efficient cell functions. This usually results in a weakened immune system and blurred vision, but in severe cases, it can lead to confusion, stroke symptoms, seizures and comas.
Various bacteria responsible for yeast and fungal infections thrive in environments with plenty of sugar, explains Aetna InteliHealth. Rashes on the genitals or vaginal discharge are not uncommon. Athlete's foot and persistent sore throat may develop. Most of these issues can be remedied by lowering blood sugar levels through medication. However, if left untreated, high blood sugar can lead to long-term health problems.