Several other drugs also showed efficacy in treatment of PTE in renal transplant recipients: theophylline, a nonselective adenosine receptor antagonist, can be used as an alternative mode of therapy of PTE; ketanserin, an antagonist of peripheral 5-HT2 receptors, can lower plasma erythropoietin levels in some chronic hemodialysis patients; and sirolimus, an immunosuppressant agent that causes marrow suppression and anemia, can be used to help treat PTE (Charfeddine et al., 2008). Here, EPO is linked to anemia.