Diabetes insipidus (DI) is characterized by excretion of large amounts of dilute urine, which disrupts your body's water regulation. To make up for lost water, you may feel the need to drink large amounts of water. You are likely to urinate frequently, even at night, which can disrupt sleep or, on occasion, cause bedwetting. Because of the excretion of abnormally large volumes of dilute urine, you may quickly become dehydrated if you do not drink enough water. Children with DI may be irritable or listless and, in some cases, may have fever, vomiting, or diarrhea. In its clinically significant forms, it is a rare disease.