ABSTRACT
The study was conducted to observe the effect of ceftriaxone alone and in combination with sulbactam against Escherichia coli. Forty Isolates of -lactamase producing Escherichia coli were collected in the microbiology laboratory Khyber Medical College, Peshawar. These were cultured and their sensitivity tests were done both with and without adding sulbactam in ceftriaxone using specially prepared antibiotic disks. NCCL zone diameter criteria was used. The disks containing the combination of ceftriaxone and sulbactam produced larger zones of inhibitions than those containing only ceftriaxone. This showed that the bacteria which had become resistant to ceftriaxone can once again become sensitive to ceftriaxone, if the inhibitor sulbactam is added