Antihypertensive Drug Therapy: Sentence Patterns But kidneys of people with hypertension tend not to make enough urine to decrease the blood volume, and this raises their blood pressure In that case, the diuretic drugs help you make more urine so the total blood volume gets lower hCTZ also lowers your blood pressure by acting directly on blood vessels, lowering their resistance to blood flow.• But kidneys of people with hypertension tend not to make enough urine to decrease the blood volume, and this raises their blood pressure. • In that case, the diuretic drugs help you make more urine so the total blood volume gets lower. • HCTZ also lowers your blood pressure by acting directly on blood vessels, lowering their resistance to blood flow. Antihypertensive Drug Therapy: Sentence Patterns