When these drugs are used in patients with eGFR <30 ml/ , close monitoring of serum potassium is required. On the other hand, withholding these drugs solely on the basis of the level of kidney function will unnecessarily deprive many patients of the CV bene ts, and perhaps even protection of the residual kidney function, that they otherwise would have received, particularly when measures could be undertaken to mitigate the risk of hyperkalemia.179,271 However, in patients with advanced CKD who are experi- encing uremic symptoms or uncontrolled hyperkalemia, it is reasonable to discontinue ACEi and ARB temporarily to allow time for kidney replacement therapy preparation.272 Practice Point 3.2.7: Mineralocorticoid receptor antagonists are effective for management of refractory hypertension but may cause hyperkalemia or a reversible decline in kidney function, particularly among patients with low eGFR. The steroidal MRAs spironolactone and eplerenone have, in small and short-term studies, been found to reduce BP in resistant hypertension (de ned as uncontrolled hypertension on 3 antihypertensive agents including a diuretic) in a popu- lation that included CKD and non-CKD171,273 and to lower albuminuria in patients with diabetes and elevated urinary Side effects, particularly hyperkalemia and decline in kidney function,274 are however a concern when added to background therapy with an ACEi, ARB, or diuretic, particularly among patients with eGFR <45 ml/min per 1.73 Thus, MRAs should not be used in patients with high risk of hyperkalemia (e.g., hypoaldosteronism or type 4 renal tubular acidosis). 