 In the ICU, fever is commonly treated with 650 mg acetaminophen every 4 hours with the hopes of reducing fever burden, thereby also reducing metabolic demand. Acetaminophen is thought to be a safe and effective antipyretic. This assumption has not been tested in the critically ill despite its widespread use. Observational studies report critically ill patients experience hypotension, sometimes severe enough to require treatment; other studies indicate acetaminophen may not be as effective at reducing fever burden in the critically ill. 