This new medication is an aldosterone blocker and acts on one of the final pathways which cause elevation in blood pressure. Given the level of this person's hypertension it is unlikely that a single agent will be sufficient to control her pressure. Is she on maximal doses of the other anihypertensives? What is her pulse? She may be able to tolerate higher doses of these meds, and not require the addition of this new agent. My main concern in terms of drug interaction is that she already is on an ARB ( benicar) which can cause hyperkalemia, and this drug can increase this risk. She should have routine levels of K checked for this reason.