What Is Aminoglycoside Toxicity?

The aminoglycosides are a set of antibiotics in common use. Although the individual drugs are beneficial in certain situations, the class as a whole carries a set of side effects which can be potentially dangerous; the term for these serious side effects is "aminoglycoside toxicity." A patient's kidney function and hearing can be affected by the drugs, and the resulting damage can be permanent.

Antibiotics are drugs that can kill bacteria, and are useful treatments for bacterial infections. Individual antibiotics can be related in structure and mode of action, and scientists place these drugs into classes. the aminoglycosides are one such group, and include medications like gentamicin, neomycin and kanamycin. As each drug within the group has similar mechanisms of action, they tend to carry the same side effects in the body.

Generally, any medical issue that arises as a result of using a medicine is called a side effect. When the side effect involves serious damage to an organ, then the side effect may be referred to as a toxic effect. Aminoglycoside toxicity typically affects either the kidneys or the ears, and the effects on the ears are more likely to be permanent than the effects on the kidneys.

When the kidneys are adversely affected by aminoglycoside treatments, the body does not remove an adequate amount of waste products from the blood. As many as 10% of people taking an aminoglycoside develop kidney problems; high doses, long courses of treatment, and increasing age of patient make this more likely. Ear damage, which is technically known as ototoxicity, occurs in about the same percentage of people, and has the same risk factors.

Certain genetic mutations can put a person at more risk than others for the development of the ear damage form of aminoglycoside toxicity. Taking other antibiotics like vancomycin, amphotericin B and cyclosporine also increase the risk of aminoglycoside toxicity, and people who already have kidney disease are more susceptible. The risk is also higher if a patient has previously taken aminoglycoside drugs.

Medical treatment can reverse the damage to the kidneys in some people, but benefits are less achievable with ototoxicity. Aminoglycoside toxicity, therefore, is a significant side effect to the aminoglycoside drugs. In addition, antibiotics in this group can also make people with muscular conditions like myasthenia gravis worse, and can slow recovery from anesthetics like succinylcholine or curare. A doctor has to balance these risks against the potential risk of worsening infection when deciding what treatment to give a patient.