- Gentamicin is a member of the aminoglycoside class of antibiotics. It is used mostly for treatment of serious infections caused mostly by gram negative bacteria such as Pseudomonas and E.coli bacteria, and also infections caused by some gram positive bacteria known to be resistant to penicillin, such as Staphylococcus and Streptococcus.
- Gentamicin is ineffective against anaerobic bacteria because its transport across bacterial cell membranes is dependent upon the presence of oxygen. Gentamicin works by inhibiting protein synthesis in susceptible bacteria by binding strongly to the bacterial ribosome at the 30S-50S interface and preventing ribosomal activity. It is bacteriocidal, meaning it causes bacterial cell death rather than just stopping bacterial growth. Because of its bacteriocidal activity, it is used to treat normal adults and children as well as patients with compromised immune systems.
- Because Gentamicin is not well absorbed from the intestinal tract, it is usually given by injection or as a topical treatment. Gentamicin is most often given as an intravenous piggy back (IVPB) infusion in the hospital, but it is available in injectable form for intramuscular use and also in a topical cream for skin infections as well as an ophthalmic solution for eye infections. The aminoglycoside family of antibiotics also includes tobramycin, amikacin and kanamycin. Gentamicin is most often used in combination with other antibiotics known to affect the bacterial cell wall. such as penicillin or vancomycin, to achieve a synergistic effect in the treatment of serious infections.
- Because Gentamicin has a number of potentially irreversible and serious side effects, it is reserved for serious infections. Nephrotoxicity or kidney damage, neurotoxicity or nerve damage, and ototoxicity or damage to ears are potentially irreversible adverse events. Due to the seriousness of these side effects, Gentamicin is prescribed based on the patient's weight, and serum concentration levels are closely monitored through periodic blood testing to ensure adequate drug levels and to avoid toxic levels.
