scholarly journals Bioavailability and pharmacokinetics of cefotaxime in Muscovy ducks

2016 ◽  
Vol 4 (1) ◽  
pp. 93 ◽  
Author(s):  
Mohamed Aboubakr
Keyword(s):  
Plasma Concentration ◽  
Plasma Concentrations ◽  
Pharmacokinetic Profile ◽  
Maximum Plasma ◽  
Mean Values ◽  
Elimination Half ◽  
Maximal Plasma ◽  
The Mean ◽  
Muscovy Ducks

The pharmacokinetic profile of cefotaxime following a single intravenous (IV) and intramuscular (IM) injection was studied in Muscovy ducks. Cefotaxime was given at a dose rate of 25 mg/kg b.wt. for both routes. After IV injection, the plasma levels of cefotaxime estimated at 0.08 h was 70.87 μg/ml, which declined gradually and cefotaxime was detected up to 10 h (0.59 μg/ml). The mean values of CL, Vdss and t1/2β of cefotaxime in muscovy ducks were 0.22 l/kg/h, 0.51 l/kg and 1.81 h, respectively. After IM injection, maximum plasma concentration (Cmax) was (14.72 μg/ml), time of maximal plasma concentration (tmax) was (2.3 h) and elimination half-life (t1/2el)was (1.77 h). Bioavailability following IM injection was 79.61%, and in vitro protein binding percent was 31.48%. A recommended IM dosage for cefotaxime in muscovy ducks would be 30 mg/kg b.wt., repeated at 12 h intervals will provide a therapeutic plasma concentrations exceeding the MIC≤0.5 µg/ml for most susceptible pathogens in ducks.

Design, Synthesis, and Pharmacokinetic Evaluation of O-Carbamoyl Tizoxanide Prodrugs

2020 ◽  
Vol 16 ◽  
Author(s):  
Xi He ◽  
Wenjun Hu ◽  
Fanhua Meng ◽  
Xingzhou Li
Keyword(s):  
Plasma Concentration ◽  
Broad Spectrum ◽  
Plasma Concentrations ◽  
Antiviral Drug ◽  
Systemic Exposure ◽  
Pharmacokinetic Profile ◽  
Hydroxyl Group ◽  
First Pass

Background: The broad-spectrum antiparasitic drug nitazoxanide (N) has been repositioned as a broad-spectrum antiviral drug. Nitazoxanide’s in vivo antiviral activities are mainly attributed to its metabolitetizoxanide, the deacetylation product of nitazoxanide. In reference to the pharmacokinetic profile of nitazoxanide, we proposed the hypotheses that the low plasma concentrations and the low system exposure of tizoxanide after dosing with nitazoxanide result from significant first pass effects in the liver. It was thought that this may be due to the unstable acyloxy bond of nitazoxanide. Objective: Tizoxanide prodrugs, with the more stable formamyl substituent attached to the hydroxyl group rather than the acetyl group of nitazoxanide, were designed with the thought that they might be more stable in plasma. It was anticipated that these prodrugs might be less affected by the first pass effect, which would improve plasma concentrations and system exposure of tizoxanide. Method: These O-carbamoyl tizoxanide prodrugs were synthesized and evaluated in a mouse model for pharmacokinetic (PK) properties and in an in vitro model for plasma stabilities. Results: The results indicated that the plasma concentration and the systemic exposure of tizoxanide (T) after oral administration of O-carbamoyl tizoxanide prodrugs were much greater than that produced by equimolar dosage of nitazoxanide. It was also found that the plasma concentration and the systemic exposure of tizoxanide glucuronide (TG) were much lower than that produced by nitazoxanide. Conclusion: Further analysis showed that the suitable plasma stability of O-carbamoyl tizoxanide prodrugs is the key factor in maximizing the plasma concentration and the systemic exposure of the active ingredient tizoxanide.

scholarly journals The Role of Pharmacokinetics in Anaesthesia: Application to Intravenous Infusions

1987 ◽  
Vol 15 (1) ◽  
pp. 7-14 ◽  
Author(s):  
D. R. Stanski
Keyword(s):  
Steady State ◽  
Plasma Concentration ◽  
Plasma Concentrations ◽  
Pharmacokinetic Profile ◽  
Volume Of Distribution ◽  
Drug Dose ◽  
Metabolic Clearance ◽  
Drug Infusion ◽  
Fixed Rate ◽  
Elimination Half

Pharmacokinetic concepts describe the relationship between drug dose and resulting plasma concentration. A drug's pharmacokinetic profile can be described by distribution and elimination half-lives, initial volume of distribution, steady-state distribution volume, and metabolic and distributional clearance. After initiating a fixed rate of drug infusion, four to five terminal elimination half-lives are required to reach a steady state of constant plasma concentration. If a loading dose is given, a steady state can be achieved more rapidly. The most rapid method of achieving a constant plasma concentration involves using a variable rate of drug infusion that adjusts for the metabolic clearance and distribution of the drug. Computer-driven infusion pumps can be used to rapidly achieve, then maintain, constant plasma concentrations of a drug.

Phase I/IIa, randomized, open-label, drug-drug interaction study of trabectedin and rifampin in patients with advanced cancer.

2013 ◽  
Vol 31 (15_suppl) ◽  
pp. e13512-e13512 ◽  
Author(s):  
Arthur P. Staddon ◽  
Trilok V. Parekh ◽  
Roland Elmar Knoblauch ◽  
Chi Keung ◽  
Apexa Bernard ◽  
...  
Keyword(s):  
Plasma Concentration ◽  
Locally Advanced ◽  
Plasma Concentrations ◽  
Systemic Exposure ◽  
Maximum Plasma ◽  
Metabolic Clearance ◽  
Open Label ◽  
Time Curve ◽  
Elimination Half ◽  
Cyp3a4 Inducer

e13512 Background: Trabectedin (Yondelis; T) is a tetrahydroisoquinoline compound initially isolated from the marine tunicate, Ecteinascidia turbinata, and currently produced synthetically. It is primarily metabolized by the cytochrome P450 (CYP)3A4 enzyme. Thus, potent inducers or inhibitors of this enzyme may alter the plasma concentrations of T. This study assessed the effects of rifampin (R), a strong CYP3A4 inducer, on the pharmacokinetics (PK) and safety of T. Methods: In this 2-way crossover study, patients (≥18 years of age) with locally advanced or metastatic disease were randomized (1:1) to receive one of the 2 treatment sequences: sequence 1: R plus T followed 28 days later by T; sequence 2: T followed 28 days later by R plus T. During each sequence, R (600 mg/day) was administered for 6 consecutive days and T (1.3 mg/m2, IV) was administered over a 3 hour infusion. Dexamethasone (20 mg, IV) was administered before T administration. PK and safety of T were evaluated with and without coadministration of R. Results: Of the 11 enrolled patients, 8 were PK evaluable. Coadministration of R with T decreased mean maximum plasma concentration (Cmax) by approximately 22% and mean area under the plasma concentration-time curve from time 0 to the last quantifiable concentration (AUClast) by approximately 31% (Table 1). Coadministration of R with T also resulted in 23% shorter elimination half-life. Overall, the safety profile of T was comparable when administered alone or with R. Conclusions: In comparison with T alone, coadministration of R resulted in reduced systemic exposure of T in these 8 patients, as measured by Cmax and AUClast. The coadministration of potent inducers of CYP3A4 with T may increase the metabolic clearance of T. Clinical trial information: NCT01273480. [Table: see text]

scholarly journals Comparison of Plasma and Intrapulmonary Concentrations of Nafithromycin (WCK 4873) in Healthy Adult Subjects

2017 ◽  
Vol 61 (9) ◽  
Author(s):  
Keith A. Rodvold ◽  
Mark H. Gotfried ◽  
Rakesh Chugh ◽  
Mugdha Gupta ◽  
H. David Friedland ◽  
...  
Keyword(s):  
Healthy Adult ◽  
Plasma Concentrations ◽  
Maximum Plasma ◽  
Total Plasma ◽  
Time Curve ◽  
The Third ◽  
Elimination Half ◽  
The Mean ◽  
Repeated Dosing ◽  
Tract Infections

ABSTRACT The nafithromycin concentrations in the plasma, epithelial lining fluid (ELF), and alveolar macrophages (AM) of 37 healthy adult subjects were measured following repeated dosing of oral nafithromycin at 800 mg once daily for 3 days. The values of noncompartmental pharmacokinetic (PK) parameters were determined from serial plasma samples collected over a 24-h interval following the first and third oral doses. Each subject underwent one standardized bronchoscopy with bronchoalveolar lavage (BAL) at 3, 6, 9, 12, 24, or 48 h after the third dose of nafithromycin. The mean ± standard deviation values of the plasma PK parameters after the first and third doses included maximum plasma concentrations (C max) of 1.02 ± 0.31 μg/ml and 1.39 ± 0.36 μg/ml, respectively; times to C max of 3.97 ± 1.30 h and 3.69 ± 1.28 h, respectively; clearances of 67.3 ± 21.3 liters/h and 52.4 ± 18.5 liters/h, respectively, and elimination half-lives of 7.7 ± 1.1 h and 9.1 ± 1.7 h, respectively. The values of the area under the plasma concentration-time curve (AUC) from time zero to 24 h postdosing (AUC0–24) for nafithromycin based on the mean or median total plasma concentrations at BAL fluid sampling times were 16.2 μg · h/ml. For ELF, the respective AUC0–24 values based on the mean and median concentrations were 224.1 and 176.3 μg · h/ml, whereas for AM, the respective AUC0–24 values were 8,538 and 5,894 μg · h/ml. Penetration ratios based on ELF and total plasma AUC0–24 values based on the mean and median concentrations were 13.8 and 10.9, respectively, whereas the ratios of the AM to total plasma concentrations based on the mean and median concentrations were 527 and 364, respectively. The sustained ELF and AM concentrations for 48 h after the third dose suggest that nafithromycin has the potential to be a useful agent for the treatment of lower respiratory tract infections. (This study has been registered at ClinicalTrials.gov under registration no. NCT02453529.)

scholarly journals Aspects of anthocyanin absorption, metabolism and pharmacokinetics in humans

2006 ◽  
Vol 19 (1) ◽  
pp. 137-146 ◽  
Author(s):  
Colin D Kay
Keyword(s):  
Biological Activities ◽  
Plasma Concentrations ◽  
Biological Significance ◽  
Future Research ◽  
Maximum Plasma ◽  
Elimination Half ◽  
Health Promoting ◽  
Clearance Kinetics ◽  
Berry Anthocyanins

AbstractInterest in the health-promoting properties of berry anthocyanins is intensifying; however, findings are primarily based onin vitrocharacteristics, leaving mechanisms associated with absorption, metabolism and pharmacokinetics largely unexplored. The present review integrates the available anthocyanin literature with that of similar flavonoids or polyphenols in order to form hypotheses regarding absorption, metabolism and clearance in humans. Of the limited available literature regarding the absorption and clearance kinetics of anthocyanins, maximum plasma concentrations are reported anywhere between 1·4 and 592 nmol/l and occur at 0·5–4 h post-consumption (doses; 68–1300 mg). Average urinary excretion is reported between 0·03 and 4 % of the ingested dose, having elimination half-lives of 1·5–3 h. In addition, much is unknown regarding the metabolism of anthocyanins. The most commonly cited conjugation reactions involved in the metabolism of other flavonoids include glucuronidation, methylation and sulfation. It is reasonable to suspect that anthocyanins are metabolised in much the same manner; however, until recently, there was little evidence to suggest that anthocyanins were metabolised to any significant extent. New evidence now suggests that anthocyanins are absorbed and transported in human serum and urine primarily as metabolites, with recent studies documenting as much as 68–80 % of anthocyanins as metabolised derivatives in human urine. Further research is required to resolve mechanisms associated with the absorption, metabolism and clearance of anthocyanins in order to establish their true biological activities and health effects. The presented evidence will hopefully focus future research, refining study design and propagating a more complete understanding of anthocyanins' biological significance in humans.

scholarly journals Pharmacokinetic and Pharmacodynamic Evaluation of Marbofloxacin in Pig against Korean Local Isolates ofActinobacillus pleuropneumoniae

2017 ◽  
Vol 2017 ◽  
pp. 1-11 ◽  
Author(s):  
Md. Akil Hossain ◽  
Hae-chul Park ◽  
Kyunghun Jeong ◽  
Yang ho Jang ◽  
Dae Gyun Kim ◽  
...  
Keyword(s):  
Body Weight ◽  
Ex Vivo ◽  
Peak Plasma ◽  
Plasma Concentrations ◽  
Antibacterial Activities ◽  
Time Intervals ◽  
Concentration Time ◽  
Elimination Half ◽  
The Mean

The pharmacokinetics of marbofloxacin in pigs after intravenous (i.v.), intramuscular (i.m.), and peroral (p.o.) administration and pharmacokinetic/pharmacodynamic indices of this drug against Korean local isolates ofActinobacillus pleuropneumoniaewere determined in this study. Marbofloxacin (2.50 mg/kg of body weight) was administered, and blood samples were collected with designated time intervals. Plasma-extracted marbofloxacin was injected into the LC-MS/MS system. The in vitro and ex vivo antibacterial activities of marbofloxacin were evaluated against 20 isolates ofA. pleuropneumoniae. The mean peak plasma concentrations (Cmax) after i.v., i.m., and p.o administration were2.60±0.10,2.59±0.12, and2.34±0.12 µg/mL at0.25±0.00,0.44±0.10, and1.58±0.40 h, respectively. The area under the plasma concentration-time curves (AUC0–24) and elimination half-lives were24.80±0.90,25.80±1.40, and23.40±5.00 h·μg/mL and8.60±0.30,12.80±1.10, and8.60±0.00 h, for i.v., i.m., and p.o. administration, correspondingly. The AUC0–24/MICs of marbofloxacin after i.v., i.m., and p.o. administration were253.86±179.91,264.1±187.16, and239.53±169.75 h, respectively. TheCmax/MIC values were26.58±18.84,26.48±18.77, and23.94±16.97, and T>MICs were42.80±1.01,36.40±1.24, and38.60±1.18 h, after i.v., i.m., and p.o. administration, respectively. Thus, marbofloxacin dosage of 2.50 mg/kg of body weight by i.v., i.m., and p.o. administration with 24 h dosing interval will provide effective treatment for the infection of pig byA. pleuropneumonia.

168 INFLUENCE OF SEVERAL INSULIN PLASMA CONCENTRATIONS ON PROGESTERONE PRODUCTION AND HISTOLOGY OF CORPORA LUTEA IN SUPEROVULATED EWES

2010 ◽  
Vol 22 (1) ◽  
pp. 242
Author(s):  
H. M. Brandão ◽  
E. H. Madureira ◽  
R. V. Sousa ◽  
F. Wouters ◽  
E. L. Vargas ◽  
...  
Keyword(s):  
Plasma Concentration ◽  
Plasma Concentrations ◽  
Cell Activity ◽  
Corpora Lutea ◽  
Mean Values ◽  
Embryo Recovery ◽  
Progesterone Production ◽  
Eosinophilic Cytoplasm ◽  
The Mean ◽  
Alloxan Monohydrate

Nutritional status is essential for the determination of mammalian reproductive performance, and insulin is one of the main indicators for such condition. This hormone is able to interfere, directly or indirectly, with CL function, leading to alterations in steroidogenic capacity and cell development and, consequently, early embryonic development. The aim of this work was to identify CL histological alterations caused by different insulin plasma concentrations in superovulated ewes, as well as their interference in CL progesterone production. Santa Inês ewes (n = 24, 4 years old) were divided into 3 treatments: control (T1, n = 9); hypoinsulinemic (T2, n = 6), and hyperinsulinemic (T3, n = 9). In order to become hypoinsulinemic, ewes were treated with a single dose of alloxan monohydrate (50 mg kg-1 i.v; Sigma-Aldich, St. Louis, MO, USA) 48 h before the beginning of the superovulation protocol, whereas the hyperinsulinemic group was treated with administrations of 20 IU of NPH human insulin at every 12 h (Biolin-N; BIOBRAS, Montes Claros, Brazil). All animals were fed corn silage and minerals ad libitum. Animals had their estrus synchronized with vaginal pessaries containing medroxyprogesterone acetate (60 mg) and were superovulated with porcine FSH (250 IU, PLUSET®, Calier, Spain) and eCG (250 IU, Novormon®, Schering-Plough, Kenilworth, NJ, USA), in a 13-day protocol. After removal of vaginal pessaries, blood samples used for quantification of progesterone and plasmatic insulin by radioimmunoassay were collected daily at 0700 h until the day before embryo recovery. Hysterectomy was performed in all groups after embryo recovery (T1: n = 3, T2: n = 6, and T3: n = 4), and ovaries were placed in buffered formalin saline. CL histological sections were evaluated by hematoxylin/eosin staining. Results were assessed by SAS statistical analysis software, using the MIXED procedure (SAS Institute Inc., Cary, NC, USA). Mean values were compared by Tukey’s test. The mean CL number was lower in T2 (5.0 ± 2.7; P < 0.05) compared with T1 (10.2 ± 5.1) and T3 (11.3 ± 3.0) animals. No histological differences were observed between treatments T1 and T3. However, CL within the T2 group had a higher number of cells with picnotic nuclei and strongly contracted eosinophilic cytoplasm. Such alterations are suggestive of cellular apoptosis. The T2 group also differed for P4 production (P < 0.01) from the second (T2: 2.23 ± 0.71 ηg mL-1; T1: 5.42 ± 4.01 ηg mL-1; T3: 6.44 ± 2.76 ηg mL-1) to the sixth day post-estrus (T2: 7.58 ± 7.00; T1: 24.79 ± 8.40; T3: 32.07 ± 0.85 ηg mL-1). The mean insulin plasma concentration differed between treatments (P < 0.01); higher concentrations were obtained in the T3 group (20.05 ± 7.50 μIU mL-1), whereas the T2 group had lower concentrations (10.18 ± 3.57 μIU mL-1) compared to controls (T1: 14.52 ± 3.80 μIU mL-1). In conclusion, low plasma concentration of insulin may restrict the response to superovulatory treatment and cause CL histological changes, suggesting a reduction in cell activity due to premature cellular senescence.

scholarly journals Pharmacokinetics and skin concentrations of lincomycin after intravenous and oral administration to cats

2013 ◽  
Vol 84 (1) ◽  
Author(s):  
Gabriela A. Albarellos ◽  
Laura Montoya ◽  
Graciela A.A. Denamiel ◽  
Sabrina M. Passini ◽  
María F. Landoni
Keyword(s):  
Plasma Concentration ◽  
Oral Administration ◽  
Intravenous Administration ◽  
Half Life ◽  
Pharmacokinetic Profile ◽  
Maximum Plasma ◽  
Elimination Half Life ◽  
Concentration Time ◽  
Elimination Half ◽  
Intravenous And Oral Administration

The aim of the present study was to describe the plasma pharmacokinetic profile and skin concentrations of lincomycin after intravenous administration of a 15% solution and oral administration of 300 mg tablets at a dosing rate of 15 mg/kg to cats. Susceptibility of staphylococci (n = 31) and streptococci (n = 23) strains isolated from clinical cases was also determined. Lincomycin plasma and skin concentrations were determined by microbiological assay using Kocuria rhizophila ATCC 9341 as test microorganism. Susceptibility was established by the antimicrobial disc diffusion test. Individual lincomycin plasma concentration–time curves were analysed by a non-compartmental approach. After intravenous administration, volume of distribution, body clearance and elimination half-life were 0.97 L/kg ± 0.15 L/kg, 0.17 L/kg ± 0.06 L/h.kg and 4.20 h ± 1.12 h, respectively. After oral administration, peak plasma concentration, time of maximum plasma concentration and bioavailability were 22.52 µg/mL ± 10.97 µg/mL, 0.80 h ± 0.11 h and 81.78% ± 24.05%, respectively. Two hours after lincomycin administration, skin concentrations were 17.26 µg/mL ± 1.32 µg/mL (intravenous) and 16.58 µg/mL ± 0.90 µg/mL (oral). The corresponding skin: plasma ratios were 2.08 ± 0.47 (intravenous) and 1.84 ± 0.97 (oral). The majority of staphylococci and streptococci tested in this study were susceptible to lincosamides (87.09% and 69.56%, respectively). In conclusion, lincomycin administered orally at the assayed dose showed a good pharmacokinetic profile, with a long elimination half-life and effective skin concentration. Therefore, it could be a good first option for treating skin infections in cats.

Pharmacokinetics, sedation and hemodynamic changes following the administration of oral transmucosal detomidine gel in cats

2020 ◽  
Vol 22 (12) ◽  
pp. 1184-1190
Author(s):  
Preston Smith ◽  
M Katherine Tolbert ◽  
Emily Gould ◽  
Alex Taylor ◽  
Heather Knych ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Geometric Mean ◽  
Venous Blood ◽  
Plasma Concentrations ◽  
Pharmacokinetic Profile ◽  
Volume Of Distribution ◽  
Maximum Plasma ◽  
Hemodynamic Variables ◽  
Elimination Half ◽  
Adult Cats

Objectives The aim of this study was to describe the pharmacokinetics of oral transmucosal (OTM) detomidine gel in healthy cats and assess its effects on sedation and hemodynamic variables. Methods Eight adult cats weighing 4.12 kg ± 0.72 received 4 mg/m2 detomidine gel onto the buccal mucosa. Level of sedation, heart rate (HR), blood pressure (BP) and respiratory rate ( f R) were assessed at predetermined intervals following administration. Blood samples for plasma detomidine concentrations and venous blood gas variables were collected from a medial saphenous catheter. Plasma detomidine concentrations were analyzed using ultra-high-pressure liquid chromatography with mass spectrometry detection, and pharmacokinetic estimates were obtained with compartmental methods. Data were analyzed using ANOVA and paired t-test or appropriate non-parametric tests. Results Sedation occurred in all cats, and was increased from baseline at 30 mins ( P <0.001). Decreases in HR occurred from 15–60 mins, ranging from 140 to 165 beats per min ( P <0.001). Blood glucose increased from 101 ± 12 mg/dl to 168 ± 27.3 mg/dl at 60 mins ( P = 0.004). Systolic blood pressure decreased from baseline (139 ± 14.8 mmHg) to 103 ± 23.0 mmHg at 60 mins ( P = 0.023). All changes abated by 120 mins. Emesis occurred in 7/7 cats within 2 mins of gel administration. Geometric mean (coefficient of variation) for clearance was 220.7 ml/min/kg (35.3 ml/min/kg), volume of distribution was 14.9 l/kg (39.9 l/kg) (both a function of bioavailability) and elimination half-life was 46.9 mins (16.0 mins). Maximum plasma concentrations of 10.5 ng/ml (35.5 ng/ml) detomidine occurred at 36.9 mins (21.5 mins). Conclusions and relevance OTM detomidine gel produced moderate sedation with minimal undesirable side effects in healthy cats, although emesis occurred in all cats. The pharmacokinetic profile supports short-term, minimally invasive sedation in this species. Further studies are warranted to assess its safety and feasibility for use in debilitated cats, or prior to general anesthesia.

Bioavailability of Three Commercial Preparations of Ibuprofen 600 mg

1988 ◽  
Vol 16 (1) ◽  
pp. 44-49 ◽  
Author(s):  
E. Källström ◽  
M. Heikinheimo ◽  
H. Quiding
Keyword(s):  
Single Dose ◽  
Plasma Concentration ◽  
Crossover Study ◽  
Healthy Volunteers ◽  
Plasma Concentrations ◽  
Analgesic Efficacy ◽  
Relative Bioavailability ◽  
Maximum Plasma ◽  
The Mean ◽  
Extent Of Absorption

The pharmacokinetic variables of ibuprofen 600 mg were investigated after administration of Brufen and compared to administration of Burana and Ibumetin. The investigation was carried out as a randomized single-dose crossover study in 17 healthy volunteers. The mean maximum plasma concentrations of ibuprofen were 58, 45 and 54 μg/ml after administration of Brufen, Burana and Ibumetin, respectively, the time to reach this being 1.4, 2.1 and 1.6 h, respectively, after administration. The differences between Brufen and Burana were significant. The relative bioavailability was very similar between Brufen and Burana but about 8% lower for Ibumetin and this difference between Brufen and Ibumetin was significant. Thus, different brands of ibuprofen may not be pharmacokinetically interchangeable and the results show that Brufen is superior to either Burana or Ibumetin when considering both the rate and extent of absorption. These findings are clinically interesting since a high and early plasma concentration of ibuprofen seems to be related to increased analgesic efficacy.

Sign in / Sign up

Export Citation Format

Share Document