Increased risk of hypotension, hyperkalemia & changes in renal function in concomitant use w/ ACE inhibitors or aliskiren. Patients who are vol- & Na-depleted by vigorous diuretic therapy, dietary salt restriction, diarrhoea or vomiting. Renovascular HTN, renal impairment & kidney transplantation. Hyperkalemia. Aortic or mitral stenosis, obstructive hypertrophic cardiomyopathy. Primary aldosteronism. May impair ability to drive or operate machinery.