Which of the following medications is a thiazide diuretic?

The correct answer is hydrochlorothiazide, which is classified as a thiazide diuretic. Thiazide diuretics are primarily used to manage hypertension and can also help reduce edema associated with heart failure or kidney disease. They work by acting on the distal convoluted tubule of the nephron in the kidneys, promoting the excretion of sodium and water, which decreases blood volume and subsequently lowers blood pressure.

Hydrochlorothiazide specifically inhibits the sodium-chloride symporter in the distal convoluted tubule, leading to increased urine output and a reduction in fluid overload. This mechanism is crucial in the treatment of conditions that respond well to diuretic therapy, such as high blood pressure and edema.

Other options, while being important medications in their respective classes, do not share the same mechanism of action or classification. Losartan, for example, is an angiotensin II receptor blocker used primarily to treat high blood pressure but does not have diuretic effects. Amlodipine is a calcium channel blocker effective for hypertension and angina but also lacks diuretic properties. Furosemide is a loop diuretic, which works differently from thiazides and is used for more severe fluid retention issues