Triamterene is a diuretic that belongs to the potassium-sparing class of drugs which are commonly used to manage hypertension and edema. It acts by blocking epithelial sodium channels in the late distal convoluted tubule of the nephron. Specifically, triamterene inhibits amiloride-sensitive sodium channels which are responsible for the reabsorption of sodium in the late distal convoluted tubule in the nephron. This primarily contributes to an increase in sodium excretion and consequentially, fluid excretion which decreases blood volume and blood pressure. Potassium secretion is indirectly affected by the inhibition of sodium reabsorption due to the elimination of the electrochemical gradient that drives potassium loss. This leads to an increase in serum potassium concentration -- a common action for potassium-sparing drugs -- and has the potential to induce hyperkalemia which can potentially lead to severe heart arrhythmias.

Triamterene Pathway References

Kidney Function References