High blood pressure is the most frequent ailment treated with diuretics. The medications work by decreasing the quantity of fluid in your blood vessels, which helps to lower your blood pressure. These drugs include: Thiazide diuretics - this group of medications includes hydrochlorothiazide (HCTZ), ethiazide (ETH), and benzthiazide (BEN). They work by reducing sodium reabsorption at several sites in the kidney, resulting in more water being flushed out of your body and the production of urine. The amount of urine produced depends on the dose of the medication; generally, patients taking thiazides require less food to stay hydrated than those who do not take these medications. Kappa-opioid receptor agonists - this group of medications includes loperamide (IMMODIUM). They work by slowing the flow of water into and out of cells, which leads to increased excretion of sodium and chloride through your kidneys. This causes you to lose more water and salt through your urine. Alpha-adrenergic blockers - this group of medications includes doxazosin (DOXAZASIN), prazosin (PRASSOL), and terazosin (TERMINOX).