Part I – That’s Odd ... Mr. Smith was a 50-year-old, otherwise healthy, white male who presented with no signs or symptoms of acute distress or complaints. He was the owner of a very busy and popular restaurant and led a very active and healthy life, including regular exercise and a well-balanced diet. He had no history of smoking, although he occasionally drank no more than one glass of red wine with dinner. For the past year, he had noticed his blood pressure was higher than usual when he checked at the machine in the local supermarket. He wondered why his blood pressure was higher despite the fact that he took good care of his health and did not have a family history of hypertension. He had no history of any previous and/or current use of medication. He made an appointment with his primary care physician and told him of his observation and concern. The doctor’s examination revealed a blood pressure of 190/110 mmHg and a heart rate of 90 bpm. The rest of the physical examination was completely unremarkable during that visit. Mr. Smith was instructed to return to the clinic for additional blood pressure measurements to be taken on two separate occasions. The subsequent readings were comparable with the initial elevated values, and a clinical diagnosis of hypertension was made. With no other remarkable findings, the doctor recommended that he continue with his active and healthy lifestyle along with monitoring his diet. In addition, the doctor prescribed hydrochlorothiazide (HCTZ), a potassium-sparing thiazide diuretic at an initial dose of 12.5 mg orally once a day as monotherapy in order to help manage the elevated blood pressure. Mr. Smith followed his doctor’s advice and was very compliant with his treatment.