The purpose of this study is to investigate the effect of plasma renin activity-guided therapy for determining hypertension treatment. Plasma renin is an enzyme in your blood that can be measured to determine your hypertension subtype. Once the subtype is known, doctors can prescribe specific medications to target your specific hypertension subtype. This study will investigate whether targeting the specific hypertension subtype helps to achieve blood pressure control sooner and with fewer medications compared to a standard fixed dose combination therapy.

Inclusion Criteria:

• Systolic BP average during at least one recent (within 1 month) clinic or emergency room visit ≥ 150 mmHg, or diastolic BP average during at least one recent (within 1 month) clinic or emergency room visit ≥ 95 mmHg
• Not currently taking BP-lowering medication
• Clinician recommends pharmacologic treatment
• Willing to make necessary study visits
• Able to be contacted by phone
• Has a primary care clinician
• At least 18 years old

Exclusion Criteria:

• Known secondary cause of hypertension
• Pregnancy
• Known diabetes, coronary artery disease or renal disease
• Known sulfonamide allergy or history of gout
• Participant's clinician recommends he/she not enroll
• Hyponatremia, hypokalemia, hypernatremia, or hyperglycemia at baseline visit
• Baseline visit systolic visit BP average < 140 mmHg and diastolic BP average < 90 mm Hg
• Resting heart rate < 55 beats per minute