When do the symptoms of gentamicin poisoning appear?
Thousands of persons receive gentamicin by IV every year, and complete their course of treatment without any noticeable signs of toxicity. However, a significant percentage of persons do suffer some ill effects. Although the development of serious symptoms is best correlated with total exposure to gentamicin (dose times days of therapy). There is no way to predict exactly when a person becomes ototoxic. This is why it is necessary to provide close monitoring of kidney function, gentamicin blood levels, and if practical, audiometric hearing tests to determine the early onset of conditions that can lead to ototoxicity. An extremely small percentage of the population is extremely sensitive (or genetically predisposed to become sensitive) to gentamicin and other aminoglycosides. A specialized laboratory test may demonstrate this sensitivity, and could potentially be used to screen persons at extreme risk. These persons usually develop ototoxicity after one or a very few doses. For the vast
