Which of the following beta-lactam antibitotics can be safely used in a patient with a history of allergy to penicillins?

MONOBACTAMS Aztreonam: It is a novel Beta-lactam antibiotic in which the other ring is missing (hence monobactam). It inhibits gram-negative enteric bacilli and H. influenzae at very low concentrations and Pseudomonas at moderate concentrations, but does not inhibit gram-positive cocci or faecal anaerobes. Thus, it is a Beta-lactam antibiotic with a spectrum resembling aminoglycosides. It is resistant to gram-negative Beta-lactamases. The main indications of aztreonam are hospitalacquired infections originating from urinary, biliary, gastrointestinal and female genital tracts. Lack of cross sensitivity with other Beta-lactam antibiotics except possibly ceftazidime is the most prominent feature of aztreonam: permiting its use in patients allergic to penicillins or cephalosporins ESSENTIALS OF MEDICAL PHARMACOLOGY K.D.TRIPATHI SIXTH EDITION PAGE NO:708