What do diuretics increase?

Diuretics are a class of medications that promote the excretion of water and electrolytes through urine. They work by inhibiting the reabsorption of sodium and water in the kidneys, specifically in the nephron. As a result, the kidneys produce more urine, leading to increased urination. This is an important mechanism for managing conditions such as hypertension, heart failure, and certain kidney disorders, where fluid balance and pressure in the circulatory system need to be carefully controlled.

The focus of diuretics on the urinary system helps in reducing excess fluid and can lead to decreased blood volume, which is beneficial in various medical treatments. The other options, including fluid retention, bowel movements, and electrolyte absorption, do not align with the primary action of diuretics in relation to their pharmacological effects.