Diabetes insipidus (DI) is a rare disorder in which the kidneys stop conserving water. Despite the similarities in name and some symptoms, it should not be confused with diabetes mellitus because these two endocrine conditions are unrelated.

In its most common form, DI is caused by damage to a part of the brain called the hypothalamus, usually due to tumors or surgery near this region. Diabetes mellitus, on the other hand, is caused by a lack of or difficulty using insulin, a hormone needed to process glucose (blood sugar) for energy.

The two most common signs of DI are increased thirst and increased urination, which are also common signs of diabetes mellitus. However, DI arises when there is a decrease in the level of a specific hormone that is responsible for instructing the kidneys to conserve water and help concentrate the urine.

Other symptoms of DI include dehydration and urine that is more clear and watery than normal. Depending on the cause, DI can be a temporary or permanent condition. Treatments may include medication, such as hormone therapy or diuretics.