Hydrochlorothiazide (HCTZ) primarily works by increasing the excretion of sodium and water from your body. It achieves this by inhibiting the sodium-chloride symporter (NCC) in the early distal convoluted tubule of your kidneys. This symporter is responsible for reabsorbing sodium and chloride ions back into your bloodstream. By blocking this reabsorption, HCTZ forces more sodium and water to be eliminated through urine.
Increased Sodium Excretion and its Consequences
This increased sodium excretion has several downstream effects. Because water follows sodium, increased sodium loss leads to a reduction in blood volume. This, in turn, lowers blood pressure. Furthermore, HCTZ also enhances the excretion of potassium and magnesium, which is why monitoring electrolyte levels is crucial during HCTZ treatment.
Additional Effects
Beyond its diuretic action, HCTZ exhibits other clinically relevant effects. Studies suggest it might influence calcium excretion, potentially reducing the risk of kidney stones in some individuals. However, individual responses vary considerably.
