A diuretic is any substance that promotes the production of urine, or, in other words, a medicine that help reduce the amount of water in the body.

There are different types of diuretics: thiazide, loop, and potassium-sparing diuretics. All of them make your body excrete more fluids as urine, but each type works differently. Alternatively, an antidiuretic such as vasopressin, or antidiuretic hormone, is an agent or drug which reduces the excretion of water in urine.

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