scholarly journals FARMACOCINÉTICA Y BIODISPONIBILIDAD ABSOLUTA DE MARBOFLOXACINA EN BÚFALOS (Bubalus bubalis)

2021 ◽  
Vol 19 (suplemento) ◽  
Author(s):  
A Anadón

The aim of this study was to evaluate the pharmacokinetic behaviour and the absolute bioavailability of marbofloxacin (MFX) in adult water buffaloes and to estimate the pharmacokinetic parameters for calculating the therapeutic dose in this animal species. Six adult buffaloes (3 males and 3 females) where treated by intravenous (IV) and subcutaneous (SC) route with a 10% experimental MFX injectable formulation at the dose of 2 mg/kg. After administration blood samples were drawn at pre-established times and MFX plasma concentrations where determined by microbiologic method. The pharmacokinetic analysis was made by compartmental analysis. After IV administration MFX presented a clearance of 198.4 ± 21.0 mL.kg.h and a half-life of elimination of 7.64 ± 3.29 h. After SC administration marbofloxacin presented a half-life of elimination of 8.5 ± 2.42 h, reaching it maximum plasma concentration (1.67 ± 0.516 μg/mL) at 1.69 ± 0.231 h, with a bioavailability of 80.8 ± 11.2 %. The estimated values of clearance and bioavailability will be employed in further studies for calculating the therapeutic dose of MFX in water buffaloes.    

2015 ◽  
Vol 10 (9) ◽  
pp. 1934578X1501000 ◽  
Author(s):  
Rosario Russo ◽  
Angelo Mancinelli ◽  
Michele Ciccone ◽  
Fabio Terruzzi ◽  
Claudio Pisano ◽  
...  

Diosmin is a naturally occurring flavonoid present in citrus fruits and other plants belonging to the Rutaceae family. It is used for the treatment of chronic venous insufficiency (CVI) for its pheblotonic and vaso-active properties, safety and tolerability as well. The aim of the current in vivo study was to investigate the pharmacokinetic profile of a branded micronized diosmin (μSMIN Plus™) compared with plain micronized diosmin in male Sprague-Dawley rats. After oral administration by gastric gavage, blood samples were collected via jugular vein catheters at regular time intervals from baseline up to 24 hours. Plasma concentrations were assessed by LC/MS. For each animal, the following pharmacokinetic parameters were calculated using a non-compartmental analysis: maximum plasma drug concentration (Cmax), time to reach Cmax (Tmax), area under the plasma concentration-time curve (AUC0-last), elimination half-life (t1/2), and relative oral bioavailability (%F). The results of the current study clearly showed an improvement in the pharmacokinetic parameters in animals treated with μSMIN Plus™ compared with animals treated with micronized diosmin. In particular, μSMIN Plus™ showed a 4-fold increased bioavailability compared with micronized diosmin. In conclusion, the results from the current study provided a preliminary pharmacokinetic profile for μSMIN Plus™, which may represent a new tool for CVI management.


2016 ◽  
Vol 4 (2) ◽  
pp. 115
Author(s):  
Nasser Ehmeza ◽  
Abdelrazzag Elmajdoub ◽  
Abubakr El-Mahmoudy

The pharmacokinetics and absolute bioavailabilities of two generics of enrofloxacin (ENRO) 10% oral solution formulation at a dose of 10 mg/Kg body weight were compared after single intracrop (i.c.) bolus administrations in reference to single intravenous (i.v.) standard ENRO administration in broilers using a randomized parallel design. The two tested formulations were Enrol® (Medmac®, Amman, Jordan) as ENRO-A and Syvaquinol® (Syva®, Leon, Spain) as ENRO-B 10% oral solutions. An HPLC assay using pure ENRO base as a standard was used to measure concentrations of ENRO from the selected sources in plasma collected at predetermined time points up to 24 hours. The pharmacokinetic analysis of the C-T data was performed using non-compartmental analysis based on statistical moment theory with the help of computerized WinNonlin program (Version 5.3, Pharsight® Corporation, St. Louis, USA). The maximum plasma concentrations (Cmax) for ENRO-A and ENRO-B were 1.61 ± 0.203 and 1.79 ± 0.283 μg/mL, respectively, attained at time to peak (Tmax) of 2 h. Elimination half-lives (t1/2β) were 8.391 ± 0.312 and 8.458 ± 0.906 h, respectively. While areas under plasma concentration-time curves (AUC0-∞), and systemic bioavailabilities (F) were 12.744 ± 2.951 and 14.354 ± 2.85 mg.h/L; and 78.96 ± 6.728 and 88.94 ± 10.89 % for ENRO-A and ENRO-B, respectively. It could be concluded that despite the superior pharmacokinetic profile of ENRO-B over ENRO-A, however, both generics were within the FDA and EMA bioequivalence acceptance range of 80%–125% and thus can be used as interchangeable therapeutic agents in chickens.


2017 ◽  
Vol 20 (2) ◽  
pp. 261-268
Author(s):  
A. Burmańczuk ◽  
T. Grabowski ◽  
T. Błądek ◽  
C. Kowalski ◽  
P. Dębiak

Abstract The aim of the study was to carry out retrospective and prospective comparative analyses of the pharmacokinetics of CEF after single intramammary (IMM) administration in cows. The prospective study (study A) was conducted on 9 dairy cows of the Polish Black-White race with clinical mastitis during the lactation period. Milk samples were collected at 2, 4, 6, 8, 10, 24, 36, 48, 72 and 84 h after single IMM administration of 250 mg of CEF to one quarter. Drug concentrations in milk samples were determined by HPLC-MS/MS technique and the results of the pharmacokinetic analysis were compared to those obtained in previous studies based on the microbiological (study B) and HPLC-UV methods (study C and D). Pharmacokinetic parameters were calculated based on adapted two-compartment model of drug distribution. One of the findings of the comparison of the analysed investigations is that the CEF kinetics determined with the microbiological method is consistent with the results obtained by the authors of this paper. Both studies yielded similar results of the key pharmacokinetic parameters related to the level of the drug distribution to tissues and elimination half-life. In the pharmacodynamic analysis, the observations in all four studies were entirely consistent and have shown lower values of T>MIC90 in healthy animals and significantly higher values in infected dairy cows. The comparison of studies A, B, C, and D revealed that the time of complete CEF wash-out of 90.90% varied and amounted to 5.7, 8.0, 2.2, and 2.2 days after administration of the drug, respectively. It was confirmed that not only the type of the analytical method but also correct sampling have a significant impact on determination of the correct value of the drug half-life after IMM administration. The comparative analysis of studies in which the milk yield was high and low allows a conclusion that this parameter in the case of CEF has no significant effect on T>MIC90.


1994 ◽  
Vol 57 (9) ◽  
pp. 796-801 ◽  
Author(s):  
LIEVE S. G. VAN POUCKE ◽  
CARLOS H. VAN PETEGHEM

The plasma pharmacokinetics and tissue penetration of sulfathiazole (ST) and sulfamethazine (SM) after intravenous and intramuscular injection in pigs were studied. Following a single intravenous dose of 40 mg ST/kg of bodyweight or 80 mg SM/kg of bodyweight, the plasma ST and SM concentrations were best fitted to a two-compartment model. The areas under the curve were 447 ± 39 and 1485 ± 41 mg/h/L, clearances were 0.090 ± 0.007 and 0.054 ± 0.001 L/kg/h, volumes of distribution were 1.16 ± 0.16 and 0.77 ± 0.06 L/kg, half-lifes in distribution phase were l.18 ± 0.57 and 0.23 ± 0.16 h and half-lifes in eliminations phase were 9.0 ± l.6 and 9.8 ± 0.6 h. When the two compounds were administered simultaneously as a single intravenous injection, the pharmacokinetic parameters for ST were not significantly different. The values for SM show statistical differences for some important parameters: α, β and the AUC0–>∞ were significantly decreased and t1/2α, Vd and CIB were significantly increased. It can be concluded that after a single intravenous injection of 40 mg/kg, sulfathiazole has a high tl/2β resulting in higher tissue concentrations. This half-life, which is higher than what is reported in the literature, is not influenced by the simultaneous presence of sulfamethazine. The tl/2β for sulfamethazine after a single intravenous injection of 80 mg/kg is comparable to the data from the literature and is not influenced by the presence of sulfathiazole. Sulfathiazole and SM were also administered simultaneously as an intramuscular injection to healthy pigs at a dosage of 40 and 80 mg/kg bodyweight. Pharmacokinetic experiments were conducted on three pigs. From this pharmacokinetic study it can be concluded that upon a single intramuscular administration of 40 mg/kg of ST and 80 mg/kg of SM the absolute bioavailability in pigs is 0.92 ± 0.04 for ST and l.01 ± 0.07 for SM. Six pigs received five intramuscular im) injections as a single dose of ST and SM every 24 h for five consecutive days for the residue study. The pigs were slaughtered at different times after the last dose was given and samples were taken from various tissues and organs. Concentrations were determined by a microbiological method and a HPTLC method. No edible tissue contained more than 100 μg/kg of the individual sulfonamides after 10 days of withdrawal. It means that adult animals which have a shorter half-life and thus lower tissue concentrations will certainly meet the economic community EC) maximum residue limits after a 10 days withdrawal period.


1988 ◽  
Vol 6 (3) ◽  
pp. 517-526 ◽  
Author(s):  
K Mross ◽  
P Maessen ◽  
W J van der Vijgh ◽  
H Gall ◽  
E Boven ◽  
...  

Pharmacokinetics of doxorubicin (DOX), epidoxorubicin (EPI), and their metabolites in plasma have been performed in eight patients receiving 40 to 56 mg/m2 of both anthracyclines as a bolus injection in two sequential cycles. Terminal half-life and volume of distribution appeared to be smaller in case of EPI, whereas plasma clearance and cumulative urinary excretion was larger in comparison to DOX. The major metabolite of DOX was doxorubicinol (Aol) followed by 7-deoxy-doxorubicinol (7d-Aolon). Metabolism to glucuronides was found in case of EPI only. The area under the curves (AUC) of the metabolites of EPI decreased in the order of the glucoronides E-glu greater than Eol-glu, 7d-Aolon greater than epirubicinol (Eol). The AUC of Eol was half of the value in its counterpart Aol. In the case of EPI, the AUC of 7d-Aolon was twice the level of that of the corresponding metabolite of DOX. The terminal half-lives of the cytostatic metabolites Aol and Eol were similar, but longer than the corresponding values of their parent drugs. Half-lives of the glucuronides (E-glu, Eol-glu) were similar to the half-life of their parent drug. 7d-Aolon had a somewhat shorter half-life in comparison to both DOX and EPI. Approximately 6.2% of EPI and 5.9% of DOX were excreted by the kidney during the initial 48 hours. Aol was found in the urine of patients treated with DOX, whereas Eol, E-glu, and Eol-glu were detected in urine of patients treated with EPI. The cumulative urinary excretion appeared to be 10.5% for EPI and its metabolites, and 6.9% for DOX and its metabolite. The plasma concentration v time curves of (7d)-aglycones showed a second peak between two and 12 hours after injection, suggesting an enterohepatic circulation for metabolites lacking the daunosamine sugar moiety. The plasma concentrations of the glucuronides were maximal at 1.2 hours for E-glu and 1.9 hours for Eol-glu. All other compounds reached their maximum plasma concentration during the first minutes after the administration of DOX and EPI. Deviating plasma kinetics were observed in one patient, probably due to prior drug administration.


1992 ◽  
Vol 26 (1) ◽  
pp. 11-13 ◽  
Author(s):  
Robin L. Davis ◽  
Ronald W. Quenzer ◽  
H. William Kelly ◽  
J. Robert Powell

OBJECTIVE: Although the effect of individual enzyme inhibitors on hepatic microsomal enzyme activity has been studied extensively, little data exist on the effects of combinations of inhibiting agents. The purpose of this study was to investigate the effect of the addition of a second hepatic oxidative enzyme inhibitor on the inhibition of metabolism in subjects already maximally inhibited by cimetidine. Ciprofloxacin was used as the second inhibitor. DESIGN: In a randomized crossover sequence, subjects received theophylline 5 mg/kg on day 6 of therapy with cimetidine 2400 mg/d, ciprofloxacin 1 g/d, both drugs, or while drug-free. SETTING: National Institutes of Health-funded General Clinical Research Center. PARTICIPANTS: Eight normal volunteers (6 men, 2 women; mean age 25.2 y). OUTCOME MEASURES: Theophylline pharmacokinetic parameters after each treatment were determined by model independent pharmacokinetic analysis. Statistical analysis of the data for differences between treatments was assessed by ANOVA for repeated measures. RESEARCH: When administered alone, ciprofloxacin and cimetidine caused a significant increase in theophylline elimination half-life and a decrease in clearance. Theophylline elimination half-life was significantly longer during combined therapy compared with either drug alone. Theophylline clearance was lower during combined treatment, although this relationship did not reach statistical significance. CONCLUSIONS: The addition of a second enzyme inhibitor in subjects receiving maximally inhibiting doses of cimetidine can produce a further decrease in the hepatic metabolism of drugs that are metabolized by the cytochrome P-450 microsomal enzyme system. As cimetidine and ciprofloxacin are frequently used together for a variety of common clinical indications, clinicians should be aware of this drug interaction and should consider that a similar effect may occur when other enzyme inhibitors are used concomitantly.


2016 ◽  
Vol 19 (10) ◽  
pp. 992-997 ◽  
Author(s):  
Gabriela A Albarellos ◽  
Laura Montoya ◽  
Sabrina M Passini ◽  
Martín P Lupi ◽  
Paula M Lorenzini ◽  
...  

Objectives The aim of this study was to determine the plasma pharmacokinetic profile, tissue concentrations and urine elimination of cefazolin in cats under surgical conditions after a single intravenous dose of 20 mg/kg. Methods Intravenous cefazolin (20 mg/kg) was administered to nine young mixed-breed cats 30 mins before they underwent surgical procedures (ovariectomy or orchiectomy). After antibiotic administration, samples from blood, some tissues and urine were taken. Cefazolin concentrations were determined in all biological matrices and pharmacokinetic parameters were estimated. Results Initial plasma concentrations were high (Cp(0), 134.80 ± 40.54 µg/ml), with fast and moderately wide distribution (distribution half-life [t½(d)] 0.16 ± 0.15 h; volume of distribution at steady state [V(d[ss])] 0.29 ± 0.10 l/kg) and rapid elimination (body clearance [ClB], 0.21 ± 0.06 l/h/kg; elimination half-life [t½], 1.18 ± 0.27 h; mean residence time 1.42 ± 0.36 h). Thirty to 60 mins after intravenous administration, cefazolin tissue concentrations ranged from 9.24 µg/ml (subcutaneous tissue) to 26.44 µg/ml (ovary). The tissue/plasma concentration ratio ranged from 0.18 (muscle) to 0.58 (ovary). Cefazolin urine concentrations were high with 84.2% of the administered dose being eliminated in the first 6 h postadministration. Conclusions and relevance Cefazolin plasma concentrations remained above a minimum inhibitory concentration of ⩽2 µg/ml up to 4 h in all the studied cats. This suggests that a single intravenous dose of 20 mg/kg cefazolin would be adequate for perioperative prophylactic use in cats.


Planta Medica ◽  
2019 ◽  
Vol 85 (06) ◽  
pp. 483-490 ◽  
Author(s):  
Phanit Songvut ◽  
Pajaree Chariyavilaskul ◽  
Mayuree Tantisira ◽  
Phisit Khemawoot

AbstractThe aim of this study was to investigate the safety and pharmacokinetic profiles of a newly developed, standardized extract of Centella asiatica (ECa 233) capsule in healthy Thai volunteers. This study was designed as an open-labeled, 2-sequence dosage, single- and repeated-dose study investigated under fasting conditions. Plasma concentrations of the parent compounds and their relative acid metabolites were measured and pharmacokinetic parameters were calculated using noncompartmental analysis. Tolerability was assessed based on physical examinations, monitoring of vital signs, clinical laboratory tests, and any observed adverse events. A key finding of this study was that the pharmacokinetics of ECa 233 in healthy volunteers did not correspond with its pharmacokinetics in animal studies. As indicated in human pharmacokinetic parameters, maximum plasma concentration and area under the curve of the parent compounds (madecassoside and asiaticoside) were very low, while their respective metabolites (madecassic acid and asiatic acid) demonstrated higher values. Based on the pharmacokinetic results observed in the dose comparison, accumulation of active metabolites after repeated dose is highly suggestive. In addition, the asiatic acid profile showed 2-fold increase in Cmax and AUC(0–t) after increasing dose from 250 to 500 mg of ECa 233. Lastly, the safety and tolerability evaluation illustrated that single and multiple doses in both 250 and 500 mg oral administration of ECa 233 were well tolerated, and none of the volunteers discontinued their participation due to adverse effects during the study.


2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 14602-14602
Author(s):  
Y. Fujisaka ◽  
Y. Fujiwara ◽  
K. Yamada ◽  
T. Shimizu ◽  
A. Horiike ◽  
...  

14602 Background: Endothelin (ET)-1 and its primary receptor, the ETA receptor, contribute to tumor cell growth, survival, angiogenesis and invasion. Atrasentan is a highly potent, selective ETA receptor antagonist. This study assessed safety and pharmacokinetics (PK) in Japanese patients with hormone refractory prostate cancer. Methods: This open-label, single-center Phase I trial evaluated the safety and PK of escalating oral atrasentan doses (2.5, 10 or 20 mg) given daily on day 1 and day 4 through 27 (except day 2 and 3). Dose-limiting toxicity (DLT) was defined as Grade 3 or greater adverse events related to study drug. Results: Eighteen patients, aged 54–74 (median; 66) were treated in cohorts of 6 patients each. The compliance of all patients was 100%. The most common toxicities were rhinitis, peripheral edema, headache, hypotension and anemia, all of which were well tolerated. These events were consistent with the anticipated vasodilatory effects or with a hemodilution effect of the study drug. DLTs were not observed. Atrasentan was rapidly absorbed following oral administration of 2.5 to 20 mg, maximum plasma concentrations averaged from 0.4 to 0.8 hours. After peaking, plasma concentrations declined bi-exponentially with a terminal half-life of approximately 25 hours. In the 10 mg dosing group, the steady-state maximum plasma concentration (Cmax) and the area under the curve (AUC0–24h) averaged 135.5 ng/mL and 533 ng h/mL, respectively. The Cmax and AUC values generally increased linearly with increasing dose after single- and multiple-dose administration. Compared to baseline, PSA decreased 50% or more in 1 patient (20 mg) and increased 25% or more in 10 patients (2.5 mg;2, 10 mg;5, 20 mg;3). The PSA of the remaining 7 patients (2.5 mg;4, 10 mg;1, 20 mg;2) ranged from < 25% increase to < 50% decrease. Fourteen patients continued on study drug in an extension study. Conclusions: Atrasentan is well tolerated, with no dose-limiting adverse events observed up to 20 mg in Japanese patients. The main adverse events are consistent with the vasodilatory effect of the drug. PK are linear and dose-proportional; the half-life is appropriate for once-daily dosing. No significant financial relationships to disclose.


1998 ◽  
Vol 32 (1) ◽  
pp. 133-136 ◽  
Author(s):  
Ching-Fa Lee ◽  
Yong-Yi Yang ◽  
Oliver Yoa-Pu Hu

Objective: The purpose of this study is to investigate the single dose pharmaco-kinetics of lithium in Taiwanese/Chinese bipolar patients for future interracial comparisons. Method: Eight bipolar patients took 900 mg of lithium carbonate after overnight fasting. Blood samples of 5 mL were taken after 15 min, 30 min, 45 min, 1 h, 2 h, 3 h, 4 h, 7 h, 9 h, 15 h, 25 h and 31 h after dosing. The computer programs CSTRIP and PCNONLIN were used for pharmacokinetic analysis. Results: The pharmacokinetic parameters obtained were as follows: Cmax, 0.970 ± 0.170 (SD) mmoi/L; Tmax, 1.59 ± 0.78 h; AUC31h = 548.9 ± 135.4 mmol.m/L; AUC = 722.6 ± 262.7 mmol.m/L; β-half-life = 16.3 ± 7.18 h; K-half-life = 0.613 ± 0.442 h; CIoral = 1.13 ± 0.39 mL/min/kg; Vd/F = 1.43 ± 0.387 L/kg. Most of the pharmacokinetic parameters were within the ranges reported in investigations of Caucasian subjects. Conclusions: This study showed that racial differences in lithium pharmacokinetics might not exist. We suggest that methodological designs, including method of blood sampling, measurement of lithium, and pharmacokinetic and statistical calculations, be standardised if future cross-ethnic comparisons are to be conducted.


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