Gentamicin

Gentamicin is an antibiotic from the group of aminoglycosides that is used to treat various types of bacterial infections. It is a mixture of substances consisting of several antibacterial compounds. These include bone infections, endocarditis, pelvic inflammatory disease, meningitis, pneumonia, urinary tract infections, and blood poisoning (sepsis). It is ineffective against gonorrhea or chlamydial infections. It can be given intravenously, by injection into a muscle, or topically. Topical formulations may be used for burns or eye infections.

Pharmacodynamics

Gentamicin is a bactericidal antibiotic that acts by binding to the 30S subunit of the bacterial ribosome, thereby interfering with protein synthesis. Gentamicin's binding to the ribosome prevents bacterial tRNA from fully binding to the ribosome, resulting in protein chain termination. This inhibits the growth and multiplication of the bacteria.

Pharmacokinetics

The oral bioavailability of gentamicin is too low for peroral administration. Therefore, gentamicin is used exclusively parenterally (injection) or on the skin. Protein binding is 0-30%. The half-life is about 3-5 hours.

Side effects

• low blood cell counts
• Allergic reactions
• Neuromuscular problems
• nerve damage (neuropathy)
• Kidney damage (nephrotoxicity)
• ear problems (ototoxicity)

Gentamicin can cause inner ear problems and kidney problems. The inner ear problems can cause problems with balance and hearing loss. Nephrotoxicity and ototoxicity are dose-dependent, with higher doses bringing a greater risk of side effects. These side effects may continue to occur even after gentamicin is stopped.

If used during pregnancy, it may harm the developing baby. However, use during breastfeeding is considered safe.

Toxicological data

LD50 (rat, oral): >5000 mg sulfate-kg-1