Diabetes insipidus is actually nothing to do with diabetes itself. This is a problem in the brain.
One of the things that controls how we pee during the day is a hormone called antidiuretic hormone, and this goes up at night, which stops us getting out of bed to pee during the night, and then goes down during the day and allows us to pee. A failure of antidiuretic hormone from the pituitary gland in the middle of the brain means that you actually lose control, not that you become incontinent, but you lose control of this backwards and forwards in terms of your kidneys producing urine.
You can end up producing a vast amount of urine, and you really can get into strife with diabetes insipidus. You can become dehydrated, your sodium, potassium, and other so-called electrolytes in your blood can go haywire. This is one of the things your doctor thinks about when you come to your doctor peeing a lot.
One of the possible diagnoses, probably the most common one is diabetes itself, but the second one they need to look for is diabetes insipidus, and it’s not that hard to diagnose.