further efforts to reduce postoperative pain require introduction of new analgesics into clinical practice.oral acetaminophen or paracetamol that is the international nonproprietary name for acetaminophen has been will know as a safe and effective analgesics and antipyretic for more than a century.In some contexts it is abbreviated as APAP for N-acetyl-para-aminophenol.However although intravenous acetaminophen has been approved in approximately 80 countries it is not urrently available in the U.S.A