Gentamicin (Garamicin, Octoret, Diakarmon) is an antibiotic belonging to the aminoglycoside group and is effective against Gram-positive and Gram-negative bacteria, including Pseudomonas aeruginosa, Klebsiella, Proteus, Serratia, and Escherichia. Gentamicin is eliminated by the kidneys. The half-life of gentamicin is 2-3 hours and steady-state levels are reached in 10-15 hours in patients with normal renal function. Gentamicin has a narrow range of therapeutic effects and therefore, it is important to monitor its levels during treatment, starting once they reach a steady state. In patients with pre-existing renal impairment, monitoring should be started earlier. Gentamicin causes renal loss of calcium and magnesium.
Measuring gentamicin concentration helps determine if antibiotic dosing is at safe and effective levels. The minimum therapeutic concentration is measured before dosing and the maximum therapeutic concentration after drug administration.
Increased concentration of gentamicin may cause nephrotoxicity. Creatinine and beta 2-microglobulin levels should be monitored daily during gentamicin treatment. Gentamicin nephrotoxicity is more likely to occur when other nephrotoxic drugs are administered together during treatment. Neonates receiving gentamicin should have a hearing assessment before starting treatment and then daily until treatment is complete. Hearing screening should also be performed on adults, if possible before starting treatment. Controlled mechanical ventilation has been shown to lower gentamicin levels in the blood.
Important Note
Laboratory test results are the most important parameter for the diagnosis and monitoring of all pathological conditions. 70%-80% of diagnostic decisions are based on laboratory tests. The correct interpretation of laboratory results allows a doctor to distinguish "healthy" from "diseased".
Laboratory test results should not be interpreted from the numerical result of a single analysis. Test results should be interpreted in relation to each individual case and family history, clinical findings, and the results of other laboratory tests and information. Your personal physician should explain the importance of your test results.
At Diagnostiki Athinon we answer any questions you may have about the test you perform in our laboratory and we contact your doctor to get the best possible medical care.