Hyperkalemia with aldosterone antagonists

The major risk related to aldosterone antagonists is hyperkalemia. Therefore, the decision for use of these agents should balance the benefit of decreasing death and hospitalization from HF and the potential risks of life-threatening hyperkalemia. Before and within one week of initiating therapy, two parameters must be assessed serum potassium and creatinine clearance (or serum creatinine). Aldosterone antagonists should not be initiated in patients with potassium concentrations greater than... 

ACE inhibitors can cause hyperkalemia because they inhibit the release of aldosterone. The effect is usually not significant in patients with normal renal function. However, in patients with impaired kidney function and/or in patients taking potassium supplements (including salt substitutes) or potassium-sparing diuretics, and especially aldosterone antagonists, hyperkalemia can occur. In two cases, hypoaldosteronism with diabetes was implicated (53,54). 

These diuretics act by reducing sodium reabsorption in the collecting duct, and hence increasing potassium retention. Spironolactone acts as a competitive antagonist of aldosterone, blocking its stimulatory effects on sodium reabsorption via the mineralocorticoid receptor. Amiloride and triamterene both inhibit ENaC, The danger of this group of diuretics is that they can induce hyperkalemia, which is particularly lilcely to occur in patients with kidney disease. 

In addition to CKD as a risk factor, other contributing factors should also be considered. This includes exposure to potassium-sparing diuretics -blockers, which work predominantly via 82-antagonistic effects to interfere with the extrarenal translocation of potassium into cells and ACEls, which may cause hyperkalemia by reducing aldosterone production. Polycitra, used for the treatment of metabolic acidosis, contains potassium citrate and should not be prescribed for patients with severe CKD. If hyperkalemia develops, management options are based on the degree to which potassium is elevated (see Chap. 50). 

Hyperkalemia Despite some reduction in the concentration of aldosterone, significant K+ retention is rarely encountered in patients with normal renal function who are not taking other drugs that cause retention. However, ACE inhibitors may cause hyperkalemia in patients with renal insufficiency or in patients taking K+-sparing diuretics, K+ supplements, adrenergic receptor antagonists, or NSAIDs. 

Urinary tract Acute renal insufficiency with hyperkalemia has been reported in a 76-year-old hypertensive woman taking both aliskiren and spironolactone [68 ]. Preexisting renal impairment and concomitant use of an aldosterone receptor antagonist were predisposing factors, and it is not surprising that the same pattern of adverse effects is seen in cases like this as have been seen with ACE inhibitors and angiotensin receptor blockers before. 

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