Malnutrition in hemodialysis patients is common and may affect as much as 40% of this population of patients. There are many causes of malnutrition and all must be considered before utilizing nutrition support to reverse the malnutrition. Intradialytic parenteral nutrition (IDPN) is a therapy that has become popular among US nephrologists despite the fact that there are no clear data that support its use or efficacy. A thorough review of published articles suggests a relationship between the use of IDPN and improved patient outcome measured by hospitalization rate and a decrease in mortality in certain subgroups. However, these studies have many confounding factors that prevent a definitive conclusion concerning the true efficacy of IDPN. This is very problematic since reimbursement changes for parenteral and enteral nutrition have been proposed by HCFA. The best recommendation that can be made for IDPN is that it may represent a useful form of nutrition support in the malnourished hemodialysis patient who has no other active disease processes, cannot ingest adequate nutrition by mouth, and has a contraindication to or a serious complication from enteral feeding. It is clearly not a therapy to be considered as the first line of nutrition support in these patients.