Are there safe alternative therapies for child with diabetes insipidus?

Water: Di don't just occur out of no where. There is usually a cause. In the brain, it could be from past head injury, infection, tumor, ischemia to the hypothalamus/pituitary gland. At the kidney, it could be due medications (lithium, demeclocyline...), kidney disease, high calcium...I recommend finding the cause and treat it. However, in general, if you maintain adequate fluid intake, symptoms is less.

DI: Diabetes insipidus is due to lack of the hormone (adh), which helps concentrate the urine, accordingly these children tend to pass large amounts of urine that is very dilute. If the child can drink enough fluid to keep up with what she/he is losing, often she/he may be able to maintain adequate fluid and electrolyte balance without the need for the hormone adh=vasopressin.