Netilmicin is a broad-spectrum aminoglycoside antibiotic that is bactericidal, meaning it kills bacteria by inhibiting their growth. It works by blocking bacterial protein synthesis, which prevents bacteria from multiplying.

Netilmicin is effective against a wide range of Gram-negative bacteria, such as E. coli, Klebsiella, Pseudomonas aeruginosa, and some Gram-positive bacteria. It is commonly used for serious infections, especially when other antibiotics are less effective.