Saturday, February 21, 2009


Gentamicin is a water-soluble antibiotic which belongs to the aminoglycoside group and is used to treat many types of bacterial infections, particularly those caused by Gram-negative bacteria. However, gentamicin is not used for Neisseria gonorrhoeae, Neisseria meningitidis or Legionella pneumophila bacterial infections. It is synthesized by Micromonospora, a genus of Gram-positive bacteria widely present in the environment (water and soil). To highlight their specific biological origins, gentamicin and other related antibiotics produced by this genus have generally their spellings ending in ~micin and not in ~mycin.

Gentamicin is a bactericidal antibiotic that works by binding the 30S subunit of the bacterial ribosome, interrupting protein synthesis. It is administered intravenously, intramuscularly or topically to treat infections. Gentamincin is a powerful antibiotic which can destroy a wide range of bacteria, normally Gram-negative bacteria, such as Pseudomonas, Proteus, Serratia, and Gram-positive Staphylococcus. Gentamicin is prescribed in the treatment of septicemia, peritonitis, pneumonia, meningitis, otitis, etc. It is also used in the treatment of some eye infections like blefaritis, conjuntivitis, dacriocistitis, etc.

Gentamicin can cause permanent loss of equilibrioception, caused by damage to the vestibular apparatus of the inner ear, usually if taken at high doses or for prolonged periods of time, but there are well documented cases in which gentamicin completely destroyed the vestibular apparatus after three to five days. A small number of affected individuals have a normally harmless mutation in their mitochondrial RNA, that allows the gentamicin to affect their cells. The cells of the ear are particularly sensitive to this.