Pharmacokinetics of ceftriaxone after intravenous, intramuscular and subcutaneous administration to domestic cats

Abstract

The pharmacokinetic properties of ceftriaxone, a third-generation cephalosporin, were investigated in five cats after single intravenous, intramuscular and subcutaneous administration at a dosage of 25 mg/kg. Ceftriaxone MICs for some gram-negative and positive strains isolated from clinical cases were determined. Efficacy predictor (t > MIC) was calculated. Serum ceftriaxone disposition was best fitted by a bicompartmental and a monocompartmental open models with first-order elimination after intravenous and intramuscular and subcutaneous dosing, respectively. After intravenous administration, distribution was fast (t1/2d 0.14 +/- 0.02 h) and moderate as reflected by the volume of distribution (V(d(ss))) of 0.57 +/- 0.22 L/kg. Furthermore, elimination was rapid with a plasma clearance of 0.37 +/- 0.13 L/h.kg and a t1/2 of 1.73 +/- 0.23 h. Peak serum concentration (Cmax), tmax and bioavailability for the intramuscular administration were 54.40 +/- 12.92 microg/mL, 0.33 +/- 0.07 h and 85.72 +/- 14.74%, respectively; and for the subcutaneous route the same parameters were 42.35 +/- 17.62 microg/mL, 1.27 +/- 0.95 h and 118.28 +/- 39.17%. Ceftriaxone MIC for gram-negative bacteria ranged from 0.0039 to >8 microg/mL and for gram-positive bacteria from 0.5 to 4 microg/mL. t > MIC was in the range 83.31-91.66% (10-12 h) of the recommended dosing interval (12 h) for Escherichia coli (MIC90 = 0.2 microg/mL).

Modelling concentrations of antimicrobial drugs: comparative pharmacokinetics of cephalosporin antimicrobials and accuracy of allometric scaling in food-producing and companion animals

“…This is confirmed by comparing the clearance for ceftazidime in cats (0.190 L/kg/h) to the glomerular filtration rate (GFR) measured in cats (renal inulin clearance) of 0.182 L/kg/h) [17]. For ceftriaxone it is reported that the mechanism of excretion in cats is through glomerular filtration and tubular secretion and/or non-renal excretion with a clearance of 0.370 L/kg/h [18], which exceeds the GFR in cats. In dogs the measured GFR (renal inulin clearance) is 0.235 L/kg/h [17].…”

In vitro and in vivo Methods to Measure the Ceftriaxone Distribution into the Rat Tail Intervertebral Disc

“…According to a previous study, the minimum inhibitory concentration (MIC) of ceftriaxone is usually less than 2 μg/mL. [1][2][3] Here, the ceftriaxone disodium salt level in discs (4.0 ± 1.7 μg/mL) was higher than MIC, and within the therapeutic level. Because ceftriaxone could penetrate into the intervertebral disc, and the level of ceftriaxone reached MIC, postoperative discitis could be prevented and the preoperative prophylaxis is meaningful.…”

“…[1][2][3][4] There is a high prevalence of postoperative infection in the intervertebral disc space, and the orthopaedist will usually use antibiotics to prevent disc infections. Prophylaxis is a way to decrease the incidence of postoperative discitis, which is an infection in intervertebral disc space.…”

Enhanced intestinal reabsorption due to reduced metabolism of ceftriaxone

“…But, reabsorption may also occur in intestine. Although the previous studies on intramuscular pharmacokinetics of ceftriaxone in cow calves (Soback et al,1988;Johal &Srivastava, 1998), camel (Goudah, 2008), cat (Abarellos et al, 2007) and goat ( Ismail et al, 2005) did not reveal any absorptionreabsorption pattern but probably blood collection at frequent interval of time may show the two phases. The veterinarians frequently use ceftriaxone intramuscularly for treatment of susceptible bacterial infections.…”