Among the symptoms that I have both while hyperglycemic and hypoglycemic are thirst and dehydration, particularly dehydration when waking up (when I've been high or low for a while without drinking because I've been asleep).
On Saturday I woke up at 3 AM, feeling dizzy and needing to pee. I went to the bathroom and went like a racehorse; I then checked my bg on dehydrated tingly fingers. 60 mg/dl.
I started wondering if maybe the kidneys make more urine in order to concentrate the blood sugar when your blood sugar is low-ish, as a defensive mechanism for sleeping people.