Comparative pharmacokinetics of aminoglycoside antibiotics

Pharmacokinetics and renal toxicity of three once-a-day doses of amikacin in cows

“…As for other aminoglycosides (Brown and Riviere, 1991), high F values after IM injection of amikacin were obtained (95%), comparable to data available in goats (Uppal et al, 1997) and calves (Carli et al, 1990;Saini and Srivastava, 1998).…”

“…The Vd AUC (0.154 ± 0.005 L/kg) and Vd ss (0.092 ± 0.004 L/kg) values obtained in this study are in agreement with the limited distribution regularly observed with aminoglycosides. However, the large Vd c value obtained in this trial (36.50 ± 2.35 L) may represent an initial concentration gradient capable of driving amikacin out of the plasma compartment, thus improving concentrations achieved in the lungs, pericardium, peritoneum, synovial fluid, kidney and urinary tract (Brown and Riviere, 1991;Chambers and Sande, 1996).…”

“…Furthermore, longer dosing intervals appear to slow the appearance of the so-called 'adaptive postexposure resistance' phenomenon, while persistent low-level exposure of a given pathogen to amikacin may markedly reduce the antimicrobial activity of this drug (Karlowsky et al, 1994). Table 1 Pharmacokinetic variables calculated for amikacin through compartmental analysis, after either the IV or IM administration of 25 mg/kg of amikacin sulphate once a day for three days It has been postulated that amikacin is less nephrotoxic than gentamicin (McHenry and Fieker, 1978;Conzelman, 1980), probably due to a lower uptake by the renal cells (Brown and Riviere, 1991), hence the lack of toxicity observed as far as the serum variables assessed are concerned. However, histological damage cannot be ruled out.…”

“…This scheme often requires pharmacokinetic expertise and close monitoring of drug serum levels and renal function to guide dosage adjustments to maximise efficacy and minimise toxicity (Pettarossi et al, 1990;Magdesian et al, 1998;Tudor et al, 1999). Other important disadvantages associated with the standard dosing of aminoglycosides include sub-therapeutic dosing, stress, inaccurate timing of drug administration and blood sampling, and misinterpretation of drug levels (Brown and Riviere, 1991). Clinicians worldwide are becoming increasingly aware that the standard dosing intervals are both labour and laboratory intensive.…”

Pharmacokinetics of Gentamicin C after IV, IM, SC and Oral Administration , C , C 1 1a and C 2 in Broiler Chickens 2a

“…Pre-column derivatization with a suitable fluorescent reagent allows for the simplest, accurate and most sensitive analysis. Derivatization of gentamicin by O-phthalaldehyde (OPA) [21], dansyl chloride [21], fluorescamine [22], 9-fluorenylmethyl chloroformate [1], 1-fluoro-2, 4-dinitrobenzene [21] and 2,4,6-trinitrobenzenesulfonic acid [23,24] were reported. However, these reagents are with drawbacks related to reagent stability, time consuming and detection sensitivity.…”