The issue does not pop up while the level of glucose in the blood is normal or a bit excessive. If it is raised, the initial symptoms start to show up. The doctors have defined what is above the norm: roughly 200 milligrams of glucose per deciliter. In other words, eleven mmol/L or more is an alarming condition. It might take weeks for at least some signs to show up. It is dangerous as the person may not recognize the high levels of sugar in the blood. Too often WC attendance (strong desire to pee), being thirsty all the time, seeing like in a fog, and feeling dizzy/exhausted are the major symptoms.