Aminoglycosides definition

The intravenous curve is, by definition, a representation of 100% bioavailability as the drug was put in its entirety into the vein. The oral curve has an area under it approximately 75% the size of the intravenous curve, and this suggests that 25% of the oral dose failed to get into the circulation. The oral bioavailability of the drug is the proportion getting into the vascular compartment, and can be measured if there is an intravenous dose curve available for the same subject at the same dose. In this example, F (the fraction bioavailable) is 0.75. It might be as high as 1.0 (100%) for some steroids, or as low as 0.1 (10%) or even less for poorly absorbed aminoglycosides. 

Numerous studies on clinical pharmacokinetic monitoring have demonstrated positive clinical outcomes. The reader is directed to a comprehensive review of the evidence to support such definitive outcomes.Some examples of positive clinical outcomes for theophylline monitoring cited in the comprehensive review include decreased length of stay and decreased toxicity. For traditional aminoglycoside monitoring, examples include decreased length of treatment,decreased length of hospital stay, ° " decreased febrile periods decreased duration to return to normal or baseline temperature, decreased duration to stabilize heart... 

The article by Miyake (Kawasaki), Maeda (Tokyo), and this writer details the long career of Sumio Umezawa devoted to the chemistry and medicinal applications of antibiotics, especially the aminocycUtols (aminoglycosides), afield dominated by Sumio and his microbiologist/biochemist brother Hamao from the earliest days of streptomycin through to practical semisynthetic analogues developed by Sumio that have enjoyed wide clinical application. The complementary articles by the two Umezawa brothers in Volume 30 of this series remain a definitive reference work on these antibiotics. 

Nephrotoxicity has been reported in 1.7% to 58% of patients receiving aminoglycoside therapy. The large variance is in part due to the use of different definitions of toxicity, variability between agents in the class, as well as the risk factors in the study population. The management of nephrotoxicity, a major contributor to the total cost of aminoglycoside therapy, was estimated to be over 4500 per case in the late 1990s. 

NAG, along with other urinary enzymes, has been used to evaluate drug induced tubular damage as in the case of acetaminophen [113], 5-aminosalicyate/ sulfasalazine in patients being treated for inflammatory bowel disease [114], and the relative nephrotoxicity of differing aminoglycoside dose schedules in neonates [115]. Assess of the urinary excretion of NAG have also been reported in hypertensive patients [116] and in patients with chronic renal failure due to various causes [117]. However, to date, it is considered to be an ancillary but non-definitive marker of renal disease. 

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