Triamterene/hydrochlorothiazide is a combination diuretic (water pill) used to treat high blood pressure and fluid retention (edema). It combines two medications: hydrochlorothiazide, a thiazide diuretic that helps the body get rid of excess salt and water, and triamterene, a potassium-sparing diuretic that helps the body retain potassium. Together, they promote the elimination of excess fluid while minimizing the risk of low potassium levels, a common side effect of diuretics. By reducing fluid buildup and lowering blood pressure, this medication helps decrease the risk of heart attacks, strokes, and kidney problems.