Used primarily in medical and research settings to treat infections caused by Gram-negative bacteria, especially Pseudomonas aeruginosa. It is effective in hospital-acquired infections such as urinary tract infections, respiratory tract infections, and septicemia. Due to its stability against many beta-lactamases, it is valuable in treating resistant bacterial strains. Commonly used in selective media in microbiology labs to isolate Pseudomonas and other resistant organisms by inhibiting the growth of competing bacteria. Its use is generally limited to parenteral administration in clinical environments due to poor oral absorption.