Azlocillin is a semi-synthetic acylureidopenicillin with broad spectrum antibacterial properties. Like the structurally related antibiotics mezlocillin and piperacillin, azlocillin is effective against the Enterobacteriaceae, including strains of K. pneumoniae that are resistant to older penicillins. Azlocillin is part of antibiotic cocktails known as PANTA (with polymyxin B ), amphotericin B , nalidixic acid, and trimethoprim and PANTAV (PANTA with vancomycin ). Azlocillin is also effective against the malarial parasite P. falciparum at concentrations similar to those used during antibiotic therapy.