Ototoxicity amikacin

Amikacin/ kanamycin Adults See footnote8 Children 15-30 mg/kg per day intravenous or intramuscular as a single daily dose Ototoxicity, nephrotoxicity Baseline audiogram, vestibular testing, Romber testing and SCr Monthly assessments of renal function and auditory or vestibular symptoms... 

Ototoxicity with both auditory and vestibulatory effects is the most serious of the adverse reactions of aminogycosides as it is mostly irreversible. Vestibular involvement manifests itself by dizziness, nystagmus, vertigo and ataxia. Cochlear toxicity results initially in high-frequency hearing loss. Amikacin more often causes cochlear damage than vestibular problems, while gentamicin and tobramycin are associated more frequently with vestibular symptoms. 

Like all aminoglycosides, amikacin is nephrotoxic and ototoxic (particularly for the auditory portion of the eighth nerve). Serum concentrations should be monitored. Target peak serum concentrations for an every-12-hours dosing regimen are... 

It is important to monitor peak and trough plasma levels (see p. 20) of gentamicin, tobramycin, netilmicin, and amikacin to avoid concentrations that cause dose-related toxicities (Figure 31.7). [Note Peak levels are defined as those obtained 1/2 to 1 hour after infusion. Trough levels are obtained immediately before the next dose.] Patient factors, such as old age, previous exposure to aminoglycosides, gender, and liver disease, tend to predispose patients to adverse reactions. The elderly are particularly susceptible to nephrotoxicity and ototoxicity. 

The same spectrum of toxicity (ototoxicity and nephrotoxicity) is shared by all members of the group, The more important and frequent interactions are pharmacodynamic. Streptomycin and gentamicin produce predominantly vestibular effects, whereas amikacin, kanamycin and neomycin primarily affect auditory function. All are rapidly excreted by the kidney,... 

Ototoxicity was observed in three of 195 patients who received amikacin (15 mg/kg/day) with either cefepime (2 g bd) or ceftazidime (2 g tds) (5). Two patients had severe loss of hearing, which persisted after drug withdrawal and resulted in permanent disability. The other had mild ototoxicity that required no action and resolved spontaneously. 

Lane AZ, Wright GE, Blair DC. Ototoxicity and nephrotoxicity of amikacin an overview of phase II and phase III experience in the United States. Am J Med 1977 62(6) 911-18. 

Differences between different aminoglycosides Ototoxicity due to amikacin is primarily cochlear however, in comparisons with equipotent dosages, ototoxicity was of the same order as that caused by gentamicin (14-16). 

In man, differences in the ototoxic risks of the currently used aminoglycosides are difficult to evaluate (20). There have been no prospective comparisons of more than two drugs using the same criteria in similar patient populations. However, several controlled comparisons of two aminoglycosides are available and provide some information. A survey of 24 such trials showed the following mean frequencies of ototoxicity gentamicin 7.7%, tobramycin 9.7%, amikacin 13.8%, netilmicin 2.3% (28). There was also a lower incidence of netilmicin-induced inner ear damage compared with tobramycin in two studies (29,30). 

Isepamicin is similar to amikacin but has better activity against strains that produce type I 6 -acetyltransferase. It can cause nephrotoxicity, vestibular toxicity, and ototoxicity. However, it is one of the less toxic of the aminoglycosides (1). The antibacterial spectrum of isepamicin includes Enterobacteriaceae and staphylococci anaerobes, Neisseriae, and streptococci are resistant (1). Isepamicin was as effective and safe as amikacin in the treatment of acute pyelonephritis in children and might prove an advantageous alternative in areas with a high incidence of resistance to other aminoglycosides (2). 

In a retrospective cost analysis, the records of 527 patients with acute leukemia were studied (11). They had been treated in a multicenter, randomized trial for febrile neutropenia with ceftazidime and amikacin plus either teicoplanin (6 mg/kg in a single dose n — 275) or vancomycin (30 mg/kg/day in 2 doses n — 252). Qinical responses were equivalent. Again the higher acquisition costs for teicoplanin were counterbalanced by the lower incidence of adverse events and easier administration, resulting in overall similar costs for both regimens. A total of 8% of patients treated with vancomycin reported adverse events compared with 3.2% of patients treated with teicoplanin. Rashes occurred in 6.0 versus 1.4% respectively. Nephrotoxicity, ototoxicity, fever, and hypotension occurred in very few patients. 

Lerner SA, Schmitt BA, Seligsohn R, Matz GJ (1986) Comparative study of ototoxicity and nephrotoxicity in patients randomly assigned to treatment with amikacin or gentamicin. Am J Med 80(6B) 98-104... 

Langhendries JP, Battisti O, Bertrand JM, Francois A, Darimont J, Ibrahim S, Tulkens PM, Bernard A, Buchet JP, Scalais E. Once-a-day adminstration of amikacin in neonates assessment of nephrotocicity and ototoxicity. Dev Pharm Ther 1993 20 220-230. 

Amikacin causes ototoxicity and nephrotoxicity. Auditory deficits are produced most commonly. 

Nausea, vomiting, diarrhea, rash, ototoxicity, nephrotoxicity, hypersensitivity reactions, neurotoxicity, superinfedions, neuromuscular blockade me as amikacin... 

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