Chlorothiazide(klor oh thye' a zide)Brand Name(s): Chlotride????Diuril??Aldochlor??(as a combination product containing Chlorothiazide, Methyldopa)??Diupres??(as a combination product containing Chlorothiazide, Reserpine)??WHY is this medicine prescribed?Chlorothiazide, a 'water pill,' is used to treat high blood pressure and fluid retention caused by various conditions, including heart disease.