REN and primary aldosteronism: The reason this is important is that medical therapy for primary aldosteronism is best with aldosterone antagonists (spironolactone, or for men, eplerenone), because they counteract the other adverse effects of spironolactone on the vasculature beyond elevation of blood pressure: inflammation, remodelling and fibrosis [32, 34, 45], On the other hand, salt and water retention based on enhanced function of the sodium channel, with low levels of renin and aldosterone, are best treated with amiloride (or possibly rostafuroxin [38]).