ABSTRACTIntroduction: The treatment of complicated intra-abdominal infections (cIAI) is increasingly challenging due to increased resistance of Gram-negative organisms. These multidrug resistant organisms lead to an increase in morbidity and mortality. This has led to renewed interest in use of older β-lactam antibiotics in combination with newer β-lactamase inhibitors. Ceftazidime-avibactam is one of the newest such combination antibiotics, which has been released for treatment of complicated intra-abdominal infections in combination with metronidazole.Areas covered: In this drug evaluation manuscript cIAI along with the chemistry, pharmacodynamics, pharmacokinetics, metabolism and clinical study results of ceftazidime-avibactam are reviewed.Expert opinion: The role of ceftazidime-avibactam in combination with metronidazole in the treatment of cIAI is still to be defined. Patients with cIAI known to be infected with Klebsiella pneumoniae carbapenemase-producing Enterobacteriaceae would be clear candidates for treatment with this agent, as would patients infected with more common types of extended-spectrum β-lactamase producing Gram-negative pathogens if a carbapenem alternative were desired. At present, it is difficult to establish a clear group of patients with cIAI for whom initial empiric therapy with this agent would be warranted.