Sepsis is the leading cause of death in critically ill and rapidness of identification is crucial to prevent circulatory collapse, multisystem organ failure, and death. The International Surviving Sepsis Guidelines supports the early implementation of empiric antimicrobial therapy. The inappropriate use or overuse of antimicrobials results in increased antibiotic resistance, increased healthcare costs, adverse drug events, and antibiotic-induced colitis. The use of a biomarker specific to bacterial sepsis would allow the clinician to diagnose sepsis early and monitor response to antimicrobial therapy, understanding the need to escalate, descalate, or discontinue therapy. Procalcitonin has been proposed as such specific biomarker; able to differentiate sepsis syndrome from systemic inflammatory response. Studies to date show mixed results regarding the effectiveness of procalcitonin to identify, stage, and monitor response to treatment of sepsis. Procalcitonin is not a gold standard in the diagnosis of sepsis; however, it is an important adjunct to other physiological clinical markers