Q: How effective is spironolactone for treating resistant hypertension? EVIDENCE-BASED ANSWER: VERY EFFECTIVE. Spironolactone reduces systolic blood pressure (SPB) by 11 to 17 mm Hg and diastolic blood pressure (DPB) by up to 6 mm Hg in patients with resistant hypertension taking 3 or more medications (strength of recommendation [SOR]: C, meta-analysis of randomized controlled trials [RCTs] of disease-oriented evidence).Corey Lyon, DO; Brigitte Utter, MD, University of Colorado, Family Medicine Residency, Denver; Kristen DeSanto, MSLS, MS, RD, University of Colorado, Health Sciences Library, Denve