Review Question - QID 108973

A 25-year-old Ashkenazi Jewish man presents to his primary care physician for a follow-up visit. 1 week ago, he presented with a chief complaint of priapism while engaging in intercourse with 2 of his partners. During that visit, it was determined that his blood pressure was 175/100 mmHg. He returns this week to have his vitals rechecked. His temperature is 99.5°F (37.5°C), pulse is 80/min, blood pressure is 182/100 mmHg, respirations are 10/min, and oxygen saturation is 98% on room air. Bloodwork is drawn and is shown below.

Serum:
Na+: 139 mEq/L
K+: 3.7 mEq/L
Cl-: 100 mEq/L
HCO3-: 28 mEq/L
Urea nitrogen: 9 mg/dL
Glucose: 122 mg/dL
Creatinine: 1.0 mg/dL
Ca2+: 9.8 mg/dL
Mg2+: 1.7 mg/dL

After a physical exam is performed, which of the following is the most appropriate initial step in management for this patient's underlying condition?