erythropoietin + pentoxifylline

A **combination therapy** of recombinant human erythropoietin (rhEPO or EPO) and pentoxifylline, typically used in the context of anemia associated with chronic kidney disease, particularly in patients with resistance to erythropoietin monotherapy. **Erythropoietin** is a glycoprotein hormone that acts as a hematopoietic growth factor, stimulating red blood cell production via the erythropoietin receptor on erythroid progenitor cells. **Pentoxifylline** is a methylxanthine-derived small molecule, a nonselective phosphodiesterase inhibitor with anti-inflammatory, anti-fibrotic, and hemorheological properties; it reduces blood viscosity and inhibits pro-inflammatory cytokines such as TNF-alpha and IFN-gamma, possibly enhancing the effectiveness of erythropoietin by ameliorating inflammation-induced resistance[1][2][4]. This combination is primarily studied and used in patients on hemodialysis or with chronic kidney disease who have anemia unresponsive or resistant to erythropoietin alone[1][2].