Gentamicin is an aminoglycoside antibiotic. It became a critical therapeutic agent due to its broad-spectrum activity against Gram-negative bacteria （e.g., Pseudomonas aeruginosa, Escherichia coli, Klebsiella） and some Gram-positive pathogens. As a bactericidal drug, gentamicin inhibits protein synthesis by binding to the 30S ribosomal subunit, disrupting mRNA translation and causing premature termination or misreading of genetic code. Clinically, it is used to treat severe infections such as sepsis, pneumonia, intra-abdominal infections, and complicated urinary tract infections. It is often combined with β-lactam antibiotics （e.g., penicillins or cephalosporins） for synergistic effects. However, its use is limited by dose-dependent nephrotoxicity and ototoxicity （hearing loss, vestibular damage）, necessitating careful monitoring of renal function and serum drug levels.