['To complement previous studies that employed indirect methods of measuring anesthesia drug waste.', 'Prospective, blinded observational study.', 'Operating rooms of a single university hospital.', 'Anesthesia providers practicing in this setting who were completely unaware of the conduct of the study.', 'All opened and unused or unusable intravenous (IV) anesthesia drugs left over at the end of each workday were collected over a randomly selected typical 2-week period.', '166 weekday cases were performed. Thirty different drugs were represented in the 157 syringes and 139 ampoules collected. Opioid waste as well as opened vials that became outdated were counted in the tally. Based on actual hospital drug acquisition costs, $1,802 of drugs were wasted during this 2-week period ($300/OR), amounting to an average cost per case of $10.86. On a cost basis, six drugs accounted for three quarters of the total wastage: phenylephrine (20.8%), propofol (14.5%), vecuronium (12.2%), midazolam (11.4%), labetalol (9.1%), and ephedrine (8.6%). Because incompletely used syringes or vials that were discarded in the trash were not measured in this analysis, the results may underestimate the total cost of drug wastage at this institution by up to 40%.'] Does drug wastage contribute significantly to the cost of routine anesthesia care?