What is the primary mechanism of action of Chlorthalidone?

Chlorthalidone primarily acts as a thiazide-like diuretic, and its main mechanism of action involves increasing sodium and chloride excretion. It does this by targeting the kidneys, specifically the distal convoluted tubule, where it interferes with the reabsorption of sodium and chloride ions. By inhibiting their reabsorption, Chlorthalidone facilitates the excretion of these electrolytes along with water, leading to an increase in urine output. This diuretic effect reduces blood volume, which consequently lowers blood pressure, making it effective in managing hypertension and fluid retention.

The focus on sodium and chloride excretion is crucial for understanding how this medication alleviates conditions like edema and high blood pressure, as these conditions are often linked to excess fluid retention. This makes the choice of increased sodium and chloride excretion as the correct answer very relevant in recognizing the primary therapeutic action of Chlorthalidone.