Diabetes insipidus (die-uh-BEE-teze in-SIP-uh-dus) is an uncommon disorder that causes an imbalance of water in the body. This imbalance leads to intense thirst even after drinking fluids (polydipsia), and excretion of large amounts of urine (polyuria).

While the names diabetes insipidus and diabetes mellitus sound similar, they're not related. Diabetes mellitus — which can occur as type 1 or type 2 — is the more common form of diabetes.

There's no cure for diabetes insipidus, but treatments are available to relieve your thirst and normalize your urine output.