IV acetaminophen is currently under development for the treatment of acute pain and fever in pediatric and adult population.The objective of this study was to systematically review the literature to assess analgesic outcomes of IV acetaminophen for acute postoperative pain in adults.studies of IV propacetamol the pro-drug to acetaminophen were not included in this study as it is being phased out of clinical practice in Europe and is not approved for use in the U.S.A>