How do diuretics reduce blood pressure ?
Diuretics target the kidneys so that increased salt and water are passed as urine. The kidneys work in two stages. First blood is filtered to remove waste products, water and salts. This leaves behind red and white blood cells. However, during this process, essential substances and nutrients are also filtered from the blood. These nutrients are then re-absorbed into the blood during the second stage process. Some conditions such as heart failure can cause more water to be re-absorbed back into the blood during this stage. Diuretics allow water and salt to pass as urine, by reducing re-absorbsion during stage two. As water is removed from the blood, the volume of blood decreases, thereby lowering blood pressure and the amount of work required by the heart.
