5种伊维菌素注射液在家兔体内的比较药动学研究

试验旨在研究5种不同处方的伊维菌素注射液在家兔体内的比较药动学特征。50只健康家兔随机分为5组,通过单次给药剂量(5 mg/kg体重)皮下注射伊维菌素注射液,3P97药动学计算软件处理血浆药物浓度—时间数据。家兔皮下注射伊维菌素注射液属于一级吸收一室开放模型。自制伊维菌素注射液的:T_1/2(Ka)(8.10±3.68) h、T_1/2(Ke)(36.34±14.63) h、T_max (22.38±8.63) h、 C_max (354.01±57.75) ng/mL、 AUC (25843±3029) ng/(mL·h)。经SPSS统计学分析软件分析显示自制伊维菌素注射液的T_1/2(Ka)、T_1/2(Ke) 无显著性差异,但C_max 分析显示与C、D存在显著性差异(P<0.05),与A、B无显著性差异(P>0.05),但明显高于A、B的C_max。AUC平均值明显高于其余4种,说明自制伊维菌素注射液在家兔体内具有吸收好,消除快,生物利用度高等优点,临床可安全使用,具有更好的抗寄生虫作用。     

伊维菌素微球在家兔体内的药动学

皮下注射伊维菌素 (IVM )微球悬液 (5 0mg/kg及 10 0mg/kg)和害获灭 (1%伊维菌素 ,0 5mg/kg) ,RP HPLC UV法定量 ,研究了IVM在家兔体内的药物动力学。害获灭皮下注射给药 ,药 时数据符合一级吸收一室开放模型 ,主要动力学参数为 :t1/2ka=7 2 4± 2 96h ;t1/2ke=36 38± 8 6 6h ;tmax=2 1 4 6± 4 82h ;Cmax=2 2 53± 2 32ng/ml;AUC =174 9± 318ng/1.h ,其动力学参数表现比较明显的个体差异 ,且与其它动物有明显差别。微球皮下注射一周后 ,血药浓度呈较稳定状态 ,到第 4 2天 (高剂量组 )和第 32天 (低剂量组 ) ,血浆中测不出H2 B1a(低于 2 5ng/ml)。以房室模型拟合 ,微球高低剂量组均符合有吸收二室开放模型 ,主要药动学参数均表现显著的个体差异。     

伊维菌素注射液含量的测定法

用紫外分光光度法测定伊维菌注射液中伊维菌素B1的含量。伊维菌素注射液溶于甲醇,于200~400nm间扫描,在238nm、245nm波长处有最大吸收峰,245nm波长处测定吸伊维菌素作对照品测得伊维菌素注射液的平均回收率为100.06%,RSD为0.24%(n=5),与《中国兽药典》规定方法比较,结果基本一致,且具有快速、准确、易操作等优点。     

伊维菌素微乳中伊维菌素的含量测定方法研究

为建立伊维菌素微乳中伊维菌素含量的高效液相色谱（HPLC）测定方法,选用Hypersil ODS2 （5 μm,4.6 mm×250 mm）色谱柱,流动相为甲醇∶乙腈∶水为35∶60∶5（V/V/V）,检测波长为244 nm,柱温为30 ℃,流速为1 mL/min进行测定。结果显示,伊维菌素在该色谱条件下,系统适应性良好,在80~320 μg/mL浓度范围内线性关系良好,回归方程为：Y=22 700X+2 510,R²=0.9998,总平均回收率为101.90%±2.94%,RSD为2.88%,对中试生产的3批伊维菌素微乳进行含量测定,RSD为1.86%。表明该含量测定方法准确可靠,重现性好,可用于伊维菌素微乳中伊维菌素含量的测定,并为该新型制剂的质量标准的制定和质量评价提供依据,也为后期的临床安全应用提供可靠的参考。     

伊维菌素微球在山羊体内的药效学研究

探讨新型制剂伊维菌素微球在山羊体内的药效学。选取32只山羊〔平均体重(27.05±1.20)kg〕,随机分成4组(Ⅰ^Ⅳ),每组7Ⅳ),每组7⁹只。Ⅰ组0.3 mg/kg体重,皮下注射伊维菌素注射液;Ⅱ和Ⅲ组3 mg/kg体重,分别皮下注射伊维菌素PLA5微球和PLGA微球混悬液;Ⅳ组作为对照组,不给药,对山羊粪便虫卵数(EPG)进行检测。Ⅰ、Ⅱ组和Ⅲ组山羊在第14天虫卵减少率均为100%,虫卵全部转阴;在给药后91 d虫卵减少率分别为0、74.3%和80.0%、;在给药后123 d分别为0、61.8%和0。伊维菌素对山羊胃肠道线虫虫卵具有较好的驱除作用,PLGA微球和PLA5微球的药效维持长达120 d左右,表现出长效作用。     

长效土霉素注射液在猪体内的生物等效性研究

研究自制长效土霉素注射液与进口长效土霉素注射液(得米先注射液)在猪体内单剂量注射的药代动力学和生物等效性,为临床应用提供参考和依据.采用双处理、双周期随即交叉试验设计.12头健康猪分为两组,分别先后单剂量肌肉注射自制长效土霉素注射液与得米先注射液,用高效液相色谱法测定血浆中土霉素的浓度,3P97软件计算药代动力学参数.自制长效土霉素注射液与参比制剂的主要药动学参数如下:AUC分别为(145.41 ±3.59)、(159.28 ±4.47) μg·mL-1·h,T1/2β分别为(84.776±2.21)、(72.740±1.95)h,Cmax分别为(3.519±1.66)、(3.924±1.34)μg/mL,Tmax分别为(1.848±0.54)、(1.760±0.41)h.采用3P97药代动力学软件分析比较AUC和Cmx90％置信区间,自制长效土霉素注射液的AUC、Cmax的90％置信区间分别为94.7％～105.2％、85.0％ ～114.6％,分别落在参比制剂的80％～125％、70％ ～143％范围内,两组参数差异不显著(P＞0.05),结果表明二者具有生物等效性.     

托芬那酸注射液在犬体内的生物等效性研究

为研究国产和进口托芬那酸注射液在犬体内的药代动力学和生物等效性,采用双处理、双周期随机交叉试验设计,将20头健康比格犬随机分成2组,按0.1 m L/kg体重肌肉分别单剂量注射受试制剂和参比制剂,采用高效液相色谱法测定血浆中托芬那酸的浓度,利用WinNonlin6.3软件计算主要药动学参数,并评价两种制剂的生物等效性。结果显示,受试制剂和参比制剂的Tmax分别为(0.2±0.1)h和(0.3±0.2)h;Cmax分别为(5.12±1.55)μg/m L和(5.38±2.04)μg/m L;AUC0-t分别为(12.1±2.97)μg·h·m L~(-1)和(12.28±3.24)μg·h·m L~(-1);AUC_(0-∞)分别为(13.38±3.10)μg·h·m L~(-1)和(13.85±3.40)μg·h·m L~(-1)。托芬那酸注射液受试制剂和参比制剂的AUC_(0-t)、AUC_(0-∞)、C_(max)、T_(max)均无显著性差异(P0.05)。双单侧t检验结果显示两种制剂生物等效,临床上可相互替代。该试验为兽医临床给药方案的制定以及合理用药提供参考。     

两种长效土霉素注射液在猪体内的生物等效性分析

研究分析长效土霉素注射液作用于猪体内的生物等效性,为临床的进一步研究提供参考依据。方法:选取24头猪,将其随机分为两组,对照组1和对照组2,对照组1注射30%长效土霉素注射液;对照组2则注射20%长效土霉素注射液。采用高效液相色谱法对猪体内的血浆土霉素浓度进行测定,分析其生物等效性。结果:对照组1和对照组2的药动学参数为:药物吸收半衰期为(0.088±0.014)h和(0.140±0.076)h;消除半衰期为(52.489±21.885)h和(36.481±21.568)h;峰浓度为(4.986±1.786)μg/ml和(5.016±0.948)μg/ml;达峰时间为(0.609±0.110)h和(0.823±0.372)h;药时曲线下面积为(112.482±18.564)mg/L.h和(109.877±19.946)mg/L.h;以20%长效土霉素注射液作为对照,30%长效土霉素注射液相对生物利用度为(105.465±26.103)%。结论:研究结果表明,两种不同浓度的长效土霉素注射液的药动学参数不具有显著差异,由此看来两种药物具有生物等效性。     

伊维菌素注射液对绵羊内外寄生虫驱除试验

用伊维菌素分低、中、高3个剂量组对60只绵羊进行了驱虫试验,结果表明,伊维菌素对绵羊鼻蝇的驱除率90％以上,虫卵减少率分别为82．4％、96．0％和96．4％。驱虫的最佳剂量为0．02ml／kg体重．     

注射用伊维菌素亚微乳的制备及其稳定性研究

以大豆磷脂S75、注射用大豆油和Poloxamer 188为辅料,采用高压匀质法,制备注射用伊维菌素亚微乳。粒度/Zeta电位测定仪测得其粒径、多分散系数和Zeta电位分别为(174.9±8.7)nm、(0.174±0.021)和(-30.9±1.06)mV;加速稳定性试验后,其外观、pH、粒径、电位和药物含量等均符合要求;局部刺激性较普通注射液轻。结果表明,注射用伊维菌素亚微乳制备工艺简单、稳定性好、刺激性小。     

不同剂型儿茶素在家兔体内的代谢动力学

取健康家兔 10只 ,随机分为 2组 ,单剂量静脉注射游离儿茶素 (Catechin)和儿茶素脂质体 (Catechin L iposom e) 2 5mg/ kg。用高效液相色谱法测定血浆中儿茶素原药质量浓度。房室模型分析表明 ,健康家兔静脉注射游离儿茶素的药时数据符合无吸收二室开放模型 [5～ 6 ] ,主要动力学参数为 :t1 /2α0 .15± 0 .0 1h,t1 /2β0 .5 8± 0 .0 2 h,维生素 C 1.4 1± 0 .0 8L ,维生素 B 2 .97± 0 .11L,Cl B3.5 3± 0 .10 L/ h,AUC16 .95± 1.5 2 L· h,K1 0 2 .5 2± 0 .2 0 h,K2 1 2 .2 5± 0 .15 h,K1 2 1.17± 0 .15 h。健康家兔静脉注射儿茶素脂质体的药时数据亦符合无吸收二室开放模型 ,主要药物动力学参数为 :t1 /2α 0 .18± 0 .0 1h,t1 /2β1.5 2± 0 .0 8h,维生素 C 1.2 5± 0 .10 L ,维生素 B 4 .4 8± 0 .2 4 1,Cl B2 .0 5± 0 .0 7L / h,AUC 2 9.2 0± 1.0 0 L· h,K1 0 1.6 4± 0 .16 h,K2 1 1.0 87±0 .0 6 h,K1 2 1.6 1± 0 .19h。试验结果表明 :儿茶素经脂质体包封后 ,药物动力学及组织分布均发生了明显的改变。     

Daily ivermectin for treatment of generalized demodicosis in dogs

Abstract Twelve dogs with generalized demodicosis were treated with oral administration of ivermectin, 0.4 mg kg^-1 of body weight given once every 24 h. Results of skin scrapings were used to determine whether administration of ivermectin should be continued or stopped. Dogs that were free of clinical signs of demodicosis 12 months after administration of ivermectin was discontinued were considered cured. Five dogs were cured. The medían duration of treatment was 15 weeks (range 5–21 weeks). Seven dogs were failures, with five relapsing 3–11. 5 months after treatment was stopped, and two having persistent demodicosis in spite of treatment. Mild ivermectin toxicosis developed in one dog after 5 weeks of treatment; side-effects resolved shortly after the treatment was stopped. Resumen Se trataron doce perros con demodicosis generalizada con ivermectina oral, 0.4 mg/Kg de peso corporal una vez cada 24 h. Se realizaron raspados cutáneos para déterminar si debia retirarse o continuar con la administración de ivermectina. Se consideraron curados aquellos perros sin sintomatologia de demodicosis 12 meses después de retirar la terapia con ivermectina. La duración medía del tratamiento con ivermectina fue de 15 semanas (rango de 5–21). Se fracasó en siete perros, con cinco recidivas a los 3–11, 5 meses después de parar la terapia y dos con demodicosis persistente a pesar del tratamiento. Un perro desarrolló una toxicosis leve a la ivermectina a las 5 semanas del tratamiento; los efectos secundarios desaparecieron al poco de retirar el tratamiento. [Medleau, L., Ristic, Z., McElveen, D.R. Daily ivermectin for treatment of generalized demodicosis in dogs (Administración díaria de ivermectina para el tratamiento de le demodicosis generalizada en el perro). Veterinary Dermatology 1996; 7 : 209–212.] Résumé Douze chiens présentant une démodécie généralisée fürent traités par administration orale d'ivermectine à la dose de 0.4 mg/kg de poids une fois par jour. Les résultats des raclages cutanés servirent à déterminar la nécessité de continuer ou d'arrêter l'administration d'ivermectine. Les chiens ne présentant aucun symptôme de démodécie 12 mois après l'arrêt de l'ivermectine fürent considérés guéris. Cinq chiens fürent guéris. La durée moyenne du traitement fut de 15 semaines (intervalles de 5 à 21 semaines. Sept cas fürent des échecs, avec 5 chiens récidivant 3 à 11, 5 mois après l'arrêt du traitement, et 2 présentant une démodécie persistante malgré le traitement. Un chien a développé une intoxication modéree après 5 semaines de traitement; les effets secondaires disparaissant rapidement après l'arrêt du traitement. [Medleau, L., Ristic, Z., McElveen, D.R. Daily ivermectin for treatment of generalized demodicosis in dogs (Administration quotidienne d'ivermectine dans le traitement de la démodécie généralisée chez le chien). Veterinary Dermatology 1996; 7 : 209–212.] Zusammenfassung Zwölf Hunde mit generalisierter Demodikose wurden mit einer oralen Verabreichung von Ivermectin in der Dosierung von 0, 4 mg/kg Körpergewicht einmal alle 24 Stunden behandelt. Die Ergebnisse der Hautgeschabsel dienten zur Bestimmung, ob die Verabreichung weiterhin erfolgen sollte oder abzubrechen sei. Hunde, die 12 Monate nach Ende der Ivermectin-Verabreichung frei von klinischen Symptomen der Demodikose waren, wurden als geheilt betrachtet. Fünf Hunde waren geheilt. Die mittlere Therapiedauer betrug 15 Wochen (Spannweite 5 bis 21 Wochen). Bei sieben Hunden versagte die Therapie, wobei fünf nach 3 bis 11, 5 Monaten nach Behandlungsende ein Rezidiv bekamen und zwei Tiere trotz der Therapie einer persistierende Demodikose zeigten. Bel einem Hund entwickelte sich 5 Wochen nach der Behandlung eine milde Ivermectin-Intoxikation; die Nebenwirkungen verschwanden kurz nach Abbruch der Therapie. [Medleau, L., Ristic, Z., McElveen, D.R. Daily ivermectin for treatment of generalized demodicosis in dogs (Tägliche Ivermectinverabreichung als Behandlung für Hunde mit generalisierter Demodikose). Veterinary Dermatology 1996; 7 : 209–212.]     

The distribution and some pharmacokinetic parameters of ivermectin in pigs

Ivermectin was injected subcutaneously into five pigs at the usual dose rate of 300 µg/kg and found to distribute well to all tissues and body fluids which were sampled 24 h post-injection. Ivermectin was detected in the contents and mucus at all levels of the gastrointestinal tract. The drug was excreted in bile, with high concentrations of the drug in the intestines and faeces. High concentrations of ivermectin were measured in skin, ears and ear wax, suggesting that the drug should be effective in the treatment of ectoparasitic infestations, particularly ear mites. The high lipid solubility of the drug may explain the high concentrations found in ear wax and skin. Ivermectin was also detected in the body fluids and tissues of an untreated pig penned with the treated animals. Direct contact appeared to be necessary for transfer of ivermectin from the treated to the untreated pig but coprophagia or urine drinking is a possible explanation.The pharmacokinetics of ivermectin administered subcutaneously at a dose rate of 300 µg/kg to six pigs were studied. There was marked individual variation in the pharmacokinetics of ivermectin. In one pig the area under the plasma concentration-time curve was particularly high. This may reflect individual variation in uptake and excretion of the drug. The mean elimination half-life of the drug was 35.2 h, suggesting that the drug is cleared slowly from pigs with drug detectable in plasma for 6–10 days. This persistence should allow a short period of protection before re-infection with parasites.     

Efficacy of daily oral ivermectin in the treatment of 10 cases of generalized demodicosis in adult dogs

Abstract The purpose of this study was to evaluate the efficacy of oral ivermectin at the dosage of 0.35 mg kg^-1 day^-1 for the treatment of generalized demodicosis in 10 adult dogs. Five of these 10 dogs had failed to respond to previous topical amitraz therapy. The mean time to obtain negative skin scrapings was 2.7 months and the mean duration of treatment was 4 months (range 2.5–8.5 months). Three patients (30%) were cured and they remained free of mites within 1 year follow-up. Two dogs (20%) were in remission for less than 6 months and five dogs (50%) relapsed. These five cases that relapsed were retreated with the above dosage of ivermectin and topical amitraz solution (1 mL Taktic/30 mL mineral oil) applied to site(s) of recurrence. One of these five cases that relapsed was in remission for more than 6 months, two dogs were in remission for less than 6 months and two dogs are still receiving treatment. Résumé— Le propos de cette étude est d'évaluer l'efficacieté de l'ivermectine par voie orale à un dosage de 0,35 mg/kg/jour dans le traitement de la démodécie généralisée chez 10 chiens adultes. Cinq de ces chiens n'avaient pas répondu à une thérapeutique topique préalable à l'amitraz. Le délai moyen pour obtenir la négativation des raclages cutanés est de 2,7 mois, et la durée moyenne de traitement est de 4 mois (extrême 2,5–8,5 mois). Trois patients (30%) ont été guéris et n'ont pas rechuté dans l'année qui a suivi le traitement. Deux des chiens (20%) ont été en rémission pendant moins de 6 mois et 5 chiens (50%) ont rechuté. Ces 5 chiens qui ont rechuté ont été retraités avec l'ivermectine à la même posologie associée à une thérapeutique topique à l'amitraz (1 ml de Taktic dans 30 ml d'huile minérale), appliquée aux sites de rechute. Un de ces 5 chiens fut en rémission pendant plus de 6 mois, 2 chiens pendant moins de 6 mois, enfin, les deux derniers reçoivent encore le traitement. [Fondati, A. Efficacy of daily oral ivermectin in the treatment of 10 cases of generalized demodicosis in adult dogs (Efficacité de l'ivermectine administrée oralement tous les jours dans le traitement de 10 cas de démodécie généralisée du chien adulte). Veterinary Dermatology 1996; 7 : 99–104.] Resumen El objetivo de este estudio fue evaluar la eficacia de la ivermectina oral con una dosis de 0.35 mg/Kg-dia para el tratamiento de la demodicosis generalizada en 10 perros adultos. Cinco de los 10 perros no habian respondido previamente a la terapia tópica con amitraz. El tiempo medio de obtención de raspados cutáneos negativos fue de 2.7 meses y la duratión media del tratamiento, de 4 meses (de 2.5 a 8.5 meses). Tres pacientes (30%) se curaron y permanecieron sin ácaros en un año de seguimiento. Dos perros (20%) estuvieron en remisión durante menos de 6 meses y en cinco (50%) se produjeron recaidas. Los animales que recayeron fueron tratados con la dosis de Ivermectina especificada arriba y solutión tópica de amitraz (1 mL Taktic/30 mL aceite mineral) aplicado a la(s) zona(s) de recidiva. Uno de los casos que recayó había estado en remisión durante 6 meses, dos perros estuvieron en remisión durante menos de 6 meses y dos estan aún bajo tratamiento. [Fondati, A. Efficacy of daily oral ivermectin in the treatment of 10 cases of generalized demodicosis in adult dogs (Eficacia de la Ivermectina oral en dosis diarias en el tratamiento de 10 casos de demodicosis generalizada en perros adultos). Veterinary Dermatology 1996; 7 : 99–104.] Zusammenfassung— Zweck dieser Studie war, die Wirksamkeit von oralem Ivermectin mit einer Dosierung von 0,35 mg/kg und Tag bei der Behandlung von generalisierter Demodikose bei 10 erwachsenen Hunden auszuwerten. 5 dieser 10 Hunden hatten auf eine vorausgegangene topische Amitraz-Therapie nicht angesprochen. Die Durchschnittszeit, um negative Hautgeschabsel zu erhalten, lag bei 2,7 Monaten, die Durchschnittsdauer der Behandlung bei 4 Monaten (mit einer Spannweite von 2,5 bis 8,5 Monaten). 3 Patienten (30%) wurden geheilt und blieben innerhalb des überwachungszeitraumes von 1 Jahr milbenfrei. Zwei Hunde (20%) waren in Remission für weniger als 6 Monate und 5 Hunde (50%) hatten ein Rezidiv. Diese fünf Rezidivfälle wurden mit der oben genannten Dosis Ivermectin und topischer Amitraz-Lösung (1 ml Taktic/30 ml Mineralöl) an den Stellen erneuter Veränderungen behandelt. Einer dieser fünf Rezidivfälle war in Remission für mehr als 6 Monate, zwei Hunde waren in Remission für weniger als 6 Monate und zwei Hunde sind immer noch unter Therapie. [Fondati, A. Efficacy of daily oral ivermectin in the treatment of 10 cases of generalized demodicosis in adult dogs (Wirksamkeit einer täglichen oralen Ivermectingabe bei der Behandlung von 10 Fällen von generalisierter Demodikose bei erwachsenen Hunden). Veterinary Dermatology 1996; 7 : 99–104.]     

Pharmacokinetics of ivermectin in sheep following pretreatment with Escherichia coli endotoxin

The comparative pharmacokinetics of ivermectin (IVM), between healthy and in Escherichia coli lipopolysaccharides (LPS) injected sheep, was investigated after an intravenous (IV) administration of a single dose of 0.2 mg/kg. Ten Suffolk Down sheep, 55 ± 3.3 kg, were distributed in two experimental groups: Group 1 (LPS): treated with three doses of 1 μg LPS/kg bw at ?24, ?16, and ?0.75 hr before IVM; group 2 (Control): treated with saline solution (SS). An IV dose of 0.2 mg IVM/kg was administered 45 min after the last injection of LPS or SS. Plasma concentrations of IVM were determined by liquid chromatography. Pharmacokinetic parameters were calculated based on non‐compartmental modeling. In healthy sheep, the values of the pharmacokinetic parameters were as follows: elimination half‐life (2.85 days), mean residence time (MRT) (2.27 days), area under the plasma concentration curve over time (AUC, 117.4 ng day^?1 ml^?1), volume of distribution (875.6 ml/kg), and clearance (187.1 ml/day). No statistically significant differences were observed when compared with the results obtained from the group of sheep treated with LPS. It is concluded that the acute inflammatory response (AIR) induced by the intravenous administration of E. coli LPS in adult sheep produced no changes in plasma concentrations or in the pharmacokinetic behavior of IVM, when it is administered intravenously at therapeutic doses.     

伊维菌素聚酯酸酐微球的制备

将2种聚酯酸酐（P（SA：RA20：80）,P（SA：RA30：70））分别与伊维菌素溶于三氯甲烷中作为有机相,以聚乙烯醇水溶液为水相,用乳化溶剂挥发法制备出2种伊维菌素聚酯酸酐微球。采用光学显微镜考察所制备微球的形态及粒径,紫外分光光度法测定载药量和包封率。结果显示,制备出的P（SA：RA30：70）／IVM微球的平均粒径为（72．240±24．747）μm,载药量为19．67％,包封率为87．70％。P（SA：RA20：80）/IVM微球的平均粒径为（64．18±26．14）μm,载药量为17．72％,包封率为87．27％。这表明采用乳化溶剂挥发法成功制备出2种伊维菌紊聚酯酸酐微球。     

Bioequivalence of ivermectin formulations in pigs and cattle

The vehicle in which endectocide compounds are formulated plays a relevant role in their absorption kinetics and resultant systemic availability. The pharmaceutical bioequivalence and comparative plasma disposition kinetics of ivermectin (IVM), following the subcutaneous administration of two injectable formulations to pigs and cattle were investigated using parallel experimental designs. Sixteen parasite-free male Duroc Jersey-Yorkshire crossbred pigs (90-110 kg) (Expt 1) and 16 parasite-free male Holstein calves (100-120 kg) (Expt 2) were divided into two groups and treated subcutaneously at either 300 (pigs) or 200 (calves) microg/kg with two different propylene glycol/glycerol formal (60: 40) based IVM formulations; in both experiments pigs or calves in Group A received the test (IVM-TEST) formulation and those in Group B were treated with the reference formulation (IVM-CONTROL). Heparinized blood samples were taken from 0 h up to either 20 (pigs) or 30 (calves) days post-treatment and plasma was extracted, derivatized and analysed by high performance liquid chromatography (HPLC) using fluorescence detection. Early detection of IVM (12 h) with a peak plasma concentration (C(max)) between 33 and 39 ng/mL was observed in pigs. The drug was detected in plasma up to 20 days post-administration of either formulation, resulting in elimination half-lives between 3.47 and 3.80 days. There were no differences between the IVM-TEST and IVM-CONTROL formulations in the kinetic parameters (except t(max)) obtained in pigs. IVM was detected in plasma between 12 h and 30 days post-administration of both formulations under investigation in cattle. The plasma disposition kinetics of IVM in calves was similar following treatment with both formulations. C(max) values (between 40.5 and 46.4 ng/mL) were achieved at 2 days post-administration of both formulations. None of the estimated kinetic parameters were statistically different between drug formulations. The injectable IVM formulations investigated were bioequivalent after their subcutaneous administration to both pigs and calves at recommended dose rates.