A 21-year-old man had a 2-year history of persistent hypertension, poorly controlled with doxazosin mesylate and nicardipine hydrochloride. He reported episodic diaphoresis and headaches at rest on a daily basis. The patient was otherwise healthy with no neurological symptoms, palpitations, constipation, abdominal pain, or other gastrointestinal complaints. He also denied fever, weight loss, cough, hemoptysis, bone pain, or other symptoms suggestive of metastatic disease. His physical examination was normal and he had no palpable neck masses. His plasma electrolyte levels and urinalysis results were normal during routine visits to his primary care physician. He had a normal electrocardiograph and no apparent cardiac anomalies.