A hospital's use and pharmacy costs of parenteral nutrition (PN) therapy before and after implementation of standardized PN formulas, prescribing guidelines, and preprinted order forms were compared. The study hospital, a large teaching institution, did not have a formal PN team. Guidelines for prescribing were promulgated by the pharmacy and therapeutics committee, the quality assurance committee, and the medical staff executive committee. Records of all patients receiving PN therapy were audited for six-month periods before and after implementation of the program. Cost data associated with decreased PN and albumin wastage, reduced labor and materials costs, inventory reduction, decreased inventory holding costs, and competitive bidding were analyzed. After implementation of this program, the number of wasted PN solutions was reduced by 55.8%, and the cost of PN solutions decreased by 36.9%. Use of albumin-containing PN solutions was reduced by 85.3%. PN solution preparation times were reduced by 66.1% (a reduction of 58.7% in preparation costs), and PN acquisition costs were reduced by 54.5%. A total annual savings of $170,722 was realized, plus a one-time cost savings of $15,632 from inventory reduction. Use of standardized parenteral nutrition formulas and prescribing guidelines can substantially decrease the cost of patient care.