Gentamicin toxicity

Tinnitus is the perception of sound, such as buzzing, hissing or pulsating noises, in the ears. Tinnitus may be caused by aspirin overdosage, furosemide or gentamicin toxicity. Tinnitus may also be an accompanying symptom of senile deafness, otosclerosis and Meniere s disease. 

As with gentamicin, toxic psychoses can occur with tobramycin (622). 

Dayal VS, Smith EL, McCain WG. Cochlear and vestibular gentamicin toxicity. A clinical study of systemic and topical usage. Arch Otolaryngol 1974 100(5) 338 0. 

Spiegel DM, Shanley PF, Molitoris BA, Mild ischemia predisposes the S3 segment to gentamicin toxicity. Kidney Ing, 1990, 38 459-64. 

Conway BP, Tabatabay CA, Campochiaro PA, D Amico DJ, Hanninen LA, Kenyon KR. Gentamicin toxicity in the primate retina. Arch Ophthalmol 1989 107 107-112. 

Youssef SHA, El-Sayed MGA, Atef M. 1987. Influence of gentamicin and rifamycin on toxicity and biotransformation of methyl parathion in rats. Dtsch Tierarztl Wochenschr 94 203-205. 

Erythromycin is considered the optimal drug for treatment of Campylobacter infections. The rate of resistance of Campylobacter to erythromycin remains low. Other advantages of this drug include ease of administration, low cost, lack of major toxicity, and narrow spectrum of activity.14 The recommended dosage for adults is 250 mg orally four times daily or 500 mg orally twice daily for 5 to 7 days. For very ill patients, treatment with gentamicin, imipenem, cefotaxime, or chloramphenicol is indicated, but susceptibility tests should be performed. 

The answer is a. (Hardman, pp 1105-1108.) The activity of streptomycin is bactericidal for the tubercle bacillus organism. Other aminoglycosides (e.g., gentamicin, tobramycin, neomycin, amikacin, and kanamycin) have activity against this organism but are seldom used clinically because of toxicity or development of resistance. 

Keniston, R.C., S. Cabellon, Jr., and K.S. Yarbrough. 1987. Pyridoxal 5 -phosphate as an antidote for cyanide, spermine, gentamicin, and dopamine toxicity an in vivo rat study. Toxicol. Appl. Pharmacol. 88 433-441. Knocke, W.R. 1981. Electroplating and cyanide wastes. Jour. Water Pollut. Contr. Feder. 53 847-851. Knowles, C.J. 1988. Cyanide utilization and degradation by microorganisms. Pages 3-15 in D. Evered and S. 

Gentamicin should be added if tolerance or moderately susceptible (MIC >0.1 g/mL) organisms are encountered streptomycin is used but can be more toxic. 

Keniston RC, Cabellon S, Yarbrouch KS. 1987. Pyridoxal 5 -phosphate as an antidote for cyanide, spermine, gentamicin, and dopamine toxicity An in vivo rat study. Toxicol Appl Pharmacol 88 433-441. 

In these reactions that mediate the nucleic acid cleavage reactions by generation of reactive oxygen species (ROS), unwanted side effects such as lipid peroxidation and free radical induced toxicity may limit their use as has been postulated in case of Fe +/ +-gentamicin complexes. ... 

Renal toxicity - Renal toxicity may be characterized by decreased creatinine clearance, cells or casts in the urine, decreased urine specific gravity, oliguria, proteinuria, or evidence of nitrogen retention. Renal damage is usually reversible. The relative nephrotoxicity of these agents is estimated to be Kanamycin = Amikacin = Gentamicin = Tobramycin Streptomycin. 

In fact elderly people have a reduced creatinine clearance, often balanced by the decline in creatinine input with a resulting normal serum creatinine. This is clinically important because drugs which are cleared through the kidneys need to be given in scaled down amounts to prevent cumulation and possible toxicity - e.g., gentamicin and other parenteral aminoglycosides, digoxin. 

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. 

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