Excessive Thirst. When it comes to Type 1 Diabetes and thirst, polydipsia can be dangerous. Prolonged dehydration can lead to nausea, dizziness, headaches and fainting. If you have Type 1 Diabetes, but have not yet been diagnosed, this dehydration has the potential to lead to Diabetic Ketoacidosis which can lead to organ failure, coma or death. Another concern is that extreme dehydration can also make your blood-sugar levels rise more quickly than normal since less urine—and glucose—is being expelled.