A 45-year-old patient on hemodialysis for one week has noted that his BP is more difficult to control. He reports good compliance with his medications, which include erythropoietin, ferrous sulfate, vancomycin, and vitamin D. His BP is 180/99 mm Hg. Most likely cause for the worsening control of his BP is?
The patient most likely has a worsening of his blood pressure due to erythropoietin. This is seen in about 33% of dialysis patients.  Vitamin D iron and vancomycin generally do not raise blood pressure.
Erythropoietin
Ferrous sulfate
Vancomycin
Vitamin D