– Tazobactam inhibits the action of bacterial ?-lactamases, especially those belonging to the SHV-1 and TEM groups. It is commonly used as its sodium salt, tazobactam sodium. Tazobactam is combined with the extended spectrum ?-lactam antibiotic piperacillin in the drug piperacillin/tazobactam, one of the preferred antibiotic treatments for nosocomial pneumonia caused by Pseudomonas aeruginosa.[medical citation needed] Tazobactam broadens the spectrum of piperacillin by making it effective against organisms that express ?-lactamase and would normally degrade piperacillin. Tazobactam is derived from the penicillin nucleus and is a penicillinic acid sulfone.