For most people, they will not be familiar with the condition medically known as diabetes insipidus, commonly referred to as DI. After all, when most people think of diabetes they think of diabetes mellitus, a condition that involves insulin. DI has nothing to do with insulin, but is a condition caused by a deficiency of ADH, or antidiuretic hormone. DI may also be caused by a sensitivity to ADH. This condition causes excessive amounts of extremely diluted urine to be produced and excreted.