Diuretics are often used to treat what condition related to fluid retention?

Diuretics are primarily used to treat heart failure because this condition often leads to fluid retention in the body due to the heart's inability to pump blood effectively. When the heart fails to function adequately, fluid can accumulate in the lungs and other tissues, resulting in symptoms such as pulmonary congestion and edema. Diuretics help eliminate excess fluid from the body by promoting its excretion through urine. This relief from fluid overload can improve breathing and reduce swelling, significantly alleviating the patient's symptoms and improving overall quality of life.

While diuretics can also be used in managing hypertension, their primary role in treating heart failure is more pronounced due to the specific nature of fluid management required in this condition. The other options, such as pneumonia and COPD, generally do not involve the same mechanism of fluid retention that would warrant the primary use of diuretics as a treatment.