Oral administration in horses refers to the delivery of medications, supplements, or nutrients via the mouth. This method is commonly used in equine veterinary medicine for its practicality and ease of use. Oral formulations can include powders, pastes, or liquids, which are designed to be palatable and easily ingested by horses. The effectiveness of oral administration depends on factors such as the horse's digestive physiology, the formulation of the product, and the consistency with which it is administered. This page compiles peer-reviewed research studies and scholarly articles that explore the techniques, efficacy, and considerations of oral administration in equine care.
Jonsdottir S, Svansson V, Stefansdottir SB, Mäntylä E, Marti E, Torsteinsdottir S.Insect bite hypersensitivity is an immunoglobulin (Ig)E-mediated dermatitis of horses initiated by bites of midges of the genus Culicoides. Culicoides spp. are not indigenous to Iceland and the prevalence of insect bite hypersensitivity is much higher in horses born in Iceland and exported as compared to Icelandic horses born in a Culicoides rich environment. Immunotherapy is therefore needed. Objective: The aim of the study was to express an allergen from Culicoides in barley grain and investigate whether an immune response could be obtained in healthy Icelandic horses by oral treatment with ...
Hussein H, Dulin J, Smanik L, Drost WT, Russell D, Wellman M, Bertone A.Our investigations evaluated the effect of VEL-0230, a highly specific irreversible inhibitor of cathepsin K (CatK). The objectives of our study were to determine whether repeated dosing of a CatK inhibitor (CatKI) produced a desired inhibition of the bone resorption biomarker (CTX-1), and document the effect of repeated dosing on bone homeostasis, structure, and dynamics of bone resorption and formation in horses. Twelve young exercising horses were randomized in a prospective, controlled clinical trial and received 4 weekly doses of a CatKI or vehicle. Baseline and poststudy nuclear scintigr...
Younkin TJ, Davis EG, Kukanich B.The primary study objective was to compare the pharmacokinetics of p.o. terbinafine alone to p.o. terbinafine administered with p.o. cimetidine in healthy adult horses. The second objective was to assess the pharmacokinetics of terbinafine when administered per rectum in two different suspensions at 30 mg/kg to adult horses. Six healthy adult horses were included in this crossover study. Plasma terbinafine concentrations were quantified with liquid chromatography and mass spectrometry. The half-life (geometric mean) was 8.38 and 10.76 h, for p.o. alone and p.o. with cimetidine, respectively....
Di Salvo A, Busechian S, Zappulla F, Marchesi MC, Pieramati C, Orvieto S, Boveri M, Predieri PG, Rueca F, Della Rocca G.A new formulation of omeprazole in gastro-resistant granules was tested with regard to its pharmacokinetics and tolerability. Twenty-four horses were randomly divided into three groups (8 horses/group) and treated, according a parallel study design, as follows: Group A untreated (control group), Group B received 4 mg/kg of omeprazole, and Group C received 12 mg/kg of omeprazole, both of which were treated orally once a day for 90 days. Blood samples, taken from Group B subjects during the 1st and the 29th day of treatment at pre-established time points, were used to determine the concentrat...
Ramsay EC, Geiser D, Carter W, Tobin T.To compare the effect of orally delivered detomidine on head posture when administered alone or in combination with two different food items, and to determine the serum concentrations of detomidine after oral delivery. Methods: Prospective randomized experimental study. Methods: Fifteen adult grade mares weighing 328-537 kg. Methods: The horses were randomly assigned to one of the three treatment groups (five horses each). The groups were given detomidine (0.06 mg kg): alone; mixed with 3 mL of an apple sauce and gum mixture; or mixed with 3 mL molasses. Head droop, measured before treatment a...
Rodríguez-Pozo ML, Armengou L, Monreal L, Viu J, Cesarini C, Jose-Cunilleras E.To assess whether an oral direct factor Xa inhibitor (DiXaI) anticoagulant drug used at the low end of the recommended dose in people achieves presumed prophylactic plasma concentrations and does not induce bleeding in horses. Methods: Experimental study. Methods: Field study. Methods: Ten healthy adult horses. Methods: A DiXaI was administered at a dose of 0.125 mg/kg every 24 h orally for 4 days. Following a wash-out period of 2 weeks, 8 of 10 horses received daily subcutaneous doses of a low molecular weight heparin (dalteparin) for 4 consecutive days at 50 IU/kg. In both trials, antifactor...
Corado CR, McKemie DS, Knych HK.Dextromethorphan is an N-methyl-D-aspartate (NMDA) non-competitive antagonist commonly used in human medicine as an antitussive. Dextromethorphan is metabolized in humans by cytochrome P450 2D6 into dextrorphan, which is reported to be more potent than the parent compound. The goal of this study is to describe the metabolism of and determine the pharmacokinetics of dextromethorphan and its major metabolites following oral administration to horses. A total of 23 horses received a single oral dose of 2 mg/kg. Blood samples were collected at time 0 and at various times up to 96 h post drug ad...
Knych HK, Harrison LM, Steinmetz SJ, Chouicha N, Kass PH.Clenbuterol, a beta2-adrenergic receptor agonist, is used therapeutically to treat respiratory conditions in the horse. However, by virtue of its mechanism of action it has been suggested that clenbuterol may also have repartitioning affects in horses and as such the potential to affect performance. Clenbuterol decreases the percent fat and increases fat-free mass following high dose administration in combination with intense exercise in horses. In the current study, microarray analysis and real-time PCR were used to study the temporal effects of low and high dose chronic clenbuterol administr...
Sykes BW, Underwood C, McGowan CM, Mills PC.This study aimed to investigate the effect of diet and dose on the pharmacokinetics of omeprazole in the horse. Six horses received two doses (1 and 4 mg/kg) of omeprazole orally once daily for 5 days. Each dose was evaluated during feeding either a high-grain/low-fibre (HG/LF) diet or an ad libitum hay (HAY) diet in a four-way crossover design. Plasma samples were collected for pharmacokinetic analysis on days 1 and 5. Plasma omeprazole concentrations were determined by ultra-high pressure liquid chromatography-mass spectrometry. In horses being fed the HG/LF diet, on day 1, the area under...
McFarlane D, Banse H, Knych HK, Maxwell LK.The objective of this study was to gain an understanding of the pharmacokinetic and pharmacodynamic properties of pergolide in horses with PPID after of long-term oral administration. Six horses with confirmed PPID were treated with pergolide (Prascend ) at 1 mg/horse po q24 h for 2 months, followed by 2 mg/horse po q24 h for 4 months. Following the last dose, plasma samples were collected for measurement of pergolide using an LC/MS/MS method and ACTH measurement using a chemiluminescent immunoassay. Noncompartmental and compartmental pharmacokinetic analyses were performed, as well as p...
Knych HK, Stanley SD, Arthur RM, McKemie DS.The use of anti-ulcer medications, such as cimetidine, ranitidine, and omeprazole, is common in performance horses. The use of these drugs is regulated in performance horses, and as such a withdrawal time is necessary prior to competition to avoid a medication violation. To the authors' knowledge, there are no reports in the literature describing repeated oral administrations of these drugs in the horse to determine a regulatory threshold and related withdrawal time recommendations. Therefore, the objective of the current study was to describe the disposition and elimination pharmacokinetics o...
Knych HK, Arthur RM, Steinmetz S, McKemie DS.Ketoprofen (KTP) is currently only available as an injectable formulation for intravenous administration to horses. The primary goal of the study reported here was to characterize the pharmacokinetics of KTP, including determination of bioavailability following oral administration of the currently available injectable formulation as well as a paste formulation. KTP was administered intravenously and orally, and blood and urine samples were collected at various time points up to 96 h. KTP enantiomer concentrations were determined using LC–MS/MS, and pharmacokinetic analyses were performed. Me...
Noble GK, Li X, Zhang D, Sillence MN.Tryptophan (TRP) is marketed as a calmative for horses despite reservations about its efficacy. The aim of this study was to measure the effect of oral TRP administration on the reaction speed of horses. Sixty mature horses were used in a two stage randomised, blind, cross-over study, receiving a placebo and an oral dose of TRP (30, 60 or 120 mg/kg body weight), before undergoing a reaction speed test. Blood samples were taken up to 96 h after TRP administration, to identify signs of acute haemolytic anaemia. Plasma TRP concentrations were increased (P <0.001) by the administration of...
Knych HK, Stanley SD, Arthur RM, McKemie DS.Cetirizine is an antihistamine used in performance horses for the treatment of hypersensitivity reactions and as such a withdrawal time is necessary prior to competition. The objective of the current study was to describe the disposition and elimination of cetirizine following oral administration in order to provide additional serum concentration data upon which appropriate regulatory recommendations can be established. Nine exercised thoroughbred horses were administered 0.4 mg/kg of cetirizine orally BID for a total of five doses. Blood samples were collected immediately prior to drug admin...
Gokbulut C, Ozuicli M, Aksit D, Aksoz E, Korkut O, Yalcinkaya M, Cirak VY.The horse milk gains increasing interest as a food product for sensitive consumers, such as children with food allergies or elderly people. We investigated the plasma and milk disposition, faecal excretion and efficacy of per os ivermectin (IVM) and pour-on eprinomectin (EPM) in horses. Ten mares were divided into two groups. The equine paste formulation of IVM and bovine pour-on formulation of EPM were administered orally and topically at dosage of 0.2 and 0.5 mg/kg bodyweight. Blood, milk and faecal samples were analysed using high-performance liquid chromatography. The plasma concentration...
Waller CC, Cawley AT, Suann CJ, Ma P, McLeod MD.Furazadrol ([1',2']isoxazolo[4',5':2,3]-5α-androstan-17β-ol) is a designer anabolic androgenic steroid that is readily available via the internet. It contains an isoxazole fused to the steroid A-ring which offers metabolic stability and noteworthy anabolic activity raising concerns over the potential for abuse of this compound in equine sports. The metabolism of furazadrol was studied by in vivo and in vitro methods for the first time. Urinary furazadrol 17-sulfate and furazadrol 17-glucuronide metabolites were detected in vivo after a controlled administration and compared with syntheticall...
Rocha JN, Cohen ND, Bordin AI, Brake CN, Giguère S, Coleman MC, Alaniz RC, Lawhon SD, Mwangi W, Pillai SD.There is currently no licensed vaccine that protects foals against Rhodococcus equi-induced pneumonia. Oral administration of live, virulent R. equi to neonatal foals has been demonstrated to protect against subsequent intrabronchial challenge with virulent R. equi. Electron beam (eBeam)-inactivated R. equi are structurally intact and have been demonstrated to be immunogenic when administered orally to neonatal foals. Thus, we investigated whether eBeam inactivated R. equi could protect foals against developing pneumonia after experimental infection with live, virulent R. equi. Foals (n = 8) w...
Knych HK, Stanley SD, Benson D, Arthur RM.Guaifenesin is an expectorant commonly used in performance horses to aid in the clearance of mucus from the airways. Guaifenesin is also a centrally acting skeletal muscle relaxant and as such is a prohibited drug with withdrawal necessary prior to competition. To the authors' knowledge, there are no reports in the literature describing single or multiple oral administrations of guaifenesin in the horse to determine a regulatory threshold and related withdrawal time. Therefore, the objective of the current study was to describe the pharmacokinetics of guaifenesin following oral administration ...
Zoller D, Lüttgenau J, Steffen S, Bollwein H.Poor uterine perfusion has been proposed as a cause of infertility in mares. The objective of this study was to investigate the effect of isosorbide dinitrate (ISDN), a nitric oxide donor, on uterine and ovarian blood flow resistance during diestrus and early pregnancy in mares. Six Trotter mares, aged 7 to 14 years, were examined daily during the first 11 days of three diestrous periods, and five of those mares were also examined during the first 11 days of two pregnancies. Six mares randomly received a placebo, a low dose (30 mg, ISDN30), or a high dose of ISDN (60 mg, ISDN60) through t...
Teixeira FA, Araújo AL, Ramalho LO, Adamkosky MS, Lacerda TF, Coelho CS.The aim of this study was to evaluate the effects of oral creatine supplementation on the athletic performance of equines used for barrel racing. Ten healthy Quarter Horses, or Quarter Horse crossbred, weighing 429.7 ± 25.3 kg and with mean age of 3.8 ± 1.2 years, were used. Animals were evaluated in four different moments (M1, M2, M3, M4), and between M3 and M4, they were supplemented with 28 g of creatine/100 kg of body weight, orally, for 45 days. Although significant alterations for LDH activity, plasma glucose and packed cell volume were observed, it was possible to conclude th...
Kusano K, Nomura M, Toju K, Ishikawa Y, Minamijima Y, Yamashita S, Nagata S.Procaterol (PCR) is a beta-2-adrenergic bronchodilator widely used in Japanese racehorses for treating lower respiratory disease. The pharmacokinetics of PCR following single intravenous (0.5 μg/kg) and oral (2.0 μg/kg) administrations were investigated in six thoroughbred horses. Plasma and urine concentrations of PCR were measured using liquid chromatography-mass spectrometry. Plasma PCR concentration following intravenous administration showed a biphasic elimination pattern. The systemic clearance was 0.47 ± 0.16 L/h/kg, the steady-state volume of the distribution was 1.21 ± 0.23 L/kg, ...
Serrano-Rodríguez JM, Gómez-Díez M, Esgueva M, Castejón-Riber C, Mena-Bravo A, Priego-Capote F, Serrano Caballero JM, Muñoz A.The pharmacokinetics and pharmacodynamics (PK/PD) of the angiotensin-converting enzyme inhibitor (ACEI) ramiprilat after intravenous (IV) and oral (PO) administration of ramipril have not been evaluated in horses. This study was designed to establish PK profiles for ramipril and ramiprilat as well as to determine the effects of ramiprilat on serum angiotensin converting enzyme (ACE) and to select the most appropriate ramipril dose that suppresses ACE activity. Six healthy horses in a cross-over design received IV ramipril 0.050 mg/kg, PO at a dose of 0 (placebo), and 0.050, 0.10, 0.20, 0.40 ...
Muñoz A, Esgueva M, Gómez-Díez M, Serrano-Caballero JM, Castejón-Riber C, Serrano-Rodríguez JM.Changes in blood pressure (BP) during acute hypertension in response to angiotensin-converting enzyme inhibitors (ACEIs) have not been investigated in normotensive horses. In this study, six healthy horses were subjected to five trials, consisting in a treadmill exercise workload of 8 m/s for 1 min, 2 h after oral administration (PO) of placebo (0 mg/kg), enalapril (2.0 mg/kg), quinapril (1.0 mg/kg), ramipril (0.2 mg/kg) or benazepril (0.5 mg/kg). Serum angiotensin converting enzyme (ACE) activity was measured and systolic (SBP) and diastolic (DBP) blood pressures were recorded...
Broux B, De Clercq D, Decloedt A, De Baere S, Devreese M, Van Der Vekens N, Ven S, Croubels S, van Loon G.Arrhythmias are common in horses. Some, such as frequent atrial or ventricular premature beats, may require long-term anti-arrhythmic therapy. In humans and small animals, sotalol hydrochloride (STL) is often used for chronic oral anti-arrhythmic therapy. STL prolongs repolarization and the effective refractory period in all cardiac tissues. No information on STL pharmacokinetics or pharmacodynamics in horses is available and the aim of this study was to evaluate the pharmacokinetics of intravenously (IV) and orally (PO) administered STL and the effects on surface electrocardiogram and left ve...
Bianco AW, Constable PD, Cooper BR, Taylor SD.Nonsteroidal anti-inflammatory drugs (NSAIDs) are an integral component of equine analgesia, yet currently available NSAIDs are both limited in their analgesic efficacy and have adverse effects. The NSAID ketorolac tromethamine (KT) is widely used in humans as a potent morphine-sparing analgesic drug but has not been fully evaluated in horses. The purpose of this study was to determine the pharmacokinetic profile of KT in horses after intravenous (i.v.), intramuscular (i.m.), and oral (p.o.) administration. Nine healthy adult horses received a single 0.5-mg/kg dose of KT via each route of admi...
Giorgi M, De Vito V, Poapolathep A, Rychshanova R, Sgorbini M, Owen H.Flupirtine (FLU) is a non-opioid analgesic drug, with no antipyretic or anti-inflammatory effects, used in the treatment of a wide range of pain states in human beings. It does not induce the side effects associated with the classical drugs used as pain relievers. The aim of this study was to evaluate the pharmacokinetic profiles of FLU after IV and PO administration in healthy horses. Six mixed breed adult mares were randomly assigned to two treatment groups using an open, single-dose, two-treatment, two-phase, paired, cross-over design (2 × 2 Latin-square). Group 1 (n = 3) received ...
Giguère S, Macpherson ML, Benson SM, Cox S, McNaughten JW, Pozor MA.Pregnancy induces several physiologic changes that might impact the bioavailability, distribution, metabolism, and excretion of drugs. The objective of this study was to determine the effects of pregnancy on the disposition of oral firocoxib in mares. Seven pony mares received oral firocoxib paste at a dose of 0.1 mg/kg during late pregnancy and again 12 to 33 days postpartum. Firocoxib concentrations were measured in plasma by HPLC with ultraviolet detection. Maximum plasma concentrations were significantly lower in pregnant (50.0 ± 21.8 ng/mL) than in postpartum (73.7 ± 25.6 ng/mL) mares. ...
Vivancos M, Barker J, Engbers S, Fischer C, Frederick J, Friedt H, Rybicka JM, Stastny T, Banse H, Cribb AE.Meloxicam, a non-steroidal anti-inflammatory drug, is approved for use in horses in several countries, but an equine formulation is not available in North America. However, meloxicam is being used in an extra-label manner in horses in Canada. The purpose of this study, therefore, was to assess the bioequivalence of an approved oral meloxicam suspension (Metacam 15 mg/mL for horses; Boehringer Ingelheim Vetmedica GmBH, Ingelheim, Germany) from the European Union with human meloxicam tablets (Meloxicam 15 mg tablets; TEVA Canada, Toronto, Ontario) compounded with molasses to improve palatability...
Garrison KL, Sahin S, Benet LZ.This study was conducted to determine the number of drugs exhibiting flip-flop pharmacokinetics following oral (p.o.) dosing from immediate-release dosage forms and if they exhibit a common characteristic that may be predicted based on BDDCS classification. The literature was searched for drugs displaying flip-flop kinetics (i.e., absorption half-life larger than elimination half-life) in mammals in PubMed, via internet search engines and reviewing drug pharmacokinetic data. Twenty two drugs were identified as displaying flip-flop kinetics in humans (13 drugs), rat (nine drugs), monkey (three ...
Guedes A, Knych H, Hood D.Laminitis is a painful disease for which adequate pain management remains a challenging and largely unmet medical need. Objective: To investigate plasma concentrations, analgesic and physiological effects of 2 doses of tramadol in horses with chronic laminitis. Methods: Nonrandomised trial. Methods: Four horses with naturally occurring chronic laminitis received 5 mg/kg bwt and then 10 mg/kg bwt tramadol orally every 12 h for one week with a one-week washout between. Noninvasive arterial blood pressure, heart and respiratory rates, intestinal sounds and forelimb off-loading frequency were ...
Seabaugh KA, Barrett MF, Rao S, McIlwraith CW, Frisbie DD.Osteoarthritis (OA) is a common problem in horses. Several oral supplements have been proposed as treatments for horses with OA. The object of this study was to evaluate the use of the oil extract from the seeds of (BO) for the treatment of experimentally induced OA in horses. OA was induced in 16, 2-5 year old horses in one middle carpal joint on Day 0; the other limb underwent a sham operation. Once daily oral treatment with BO or placebo was initiated on Day 0 and continued to Day 70. All horses were exercised 5 days a week starting on Day 14 through Day 70. The horses were evaluated every...
Pellegrini-Masini A, Poppenga RH, Sweeney RW.An injectable preparation of flunixin meglumine was administered orally and intravenously at a dose of 1.1 mg/kg to six healthy adult horses in a cross-over design. Flunixin meglumine was detected in plasma within 15 min of administration and peak plasma concentrations were observed 45-60 min after oral administration. Mean bioavailability of the oral drug was 71.9 +/- 26.0%, with an absorption half-life of 0.76 h. The apparent elimination half-life after oral administration was 2.4 h. The injectable preparation of flunixin meglumine is suitable for oral administration to horses.
Bergin BJ, Pierce SW, Bramlage LR, Stromberg A.Hyaluronan (HA) has been used to treat joint disease via intra-articular, i.v. and oral administration. The efficacy of intra-articular and i.v. use has been evaluated but the oral route has yet to be examined. Objective: To determine the effect of oral hyaluronan gel on joint effusion following arthroscopic surgery for osteochondritis dissecans (OCD) of the tarsocrural joint of yearling Thoroughbreds. Methods: Forty-eight yearlings diagnosed with unilateral or bilateral osteochondritis dessicans (OCD) of the tarsus were arbitrarily chosen prior to arthroscopic surgery. The yearlings were incl...
Mainguy-Seers S, Bessonnat A, Picotte K, Lavoie JP.Inhaled corticosteroids are effective in the treatment of equine asthma. A recent study reported that nebulisation of injectable dexamethasone had low systemic bioavailability in healthy horses and could represent a cost-effective therapy for equine inflammatory lung diseases. Objective: To determine the effects of dexamethasone nebulisation on lung function in severe asthmatic horses. It was hypothesised that dexamethasone administered by nebulisation would be more effective than the same dose administered orally. Methods: Randomised blinded experimental study in severe asthmatic horses. Meth...
Torbert BJ, Kramer BS, Klei TR.A controlled test was used in ponies to compare the antiparasitic efficacy of ivermectin (22,23-dihydro-avermectin B1) in an injectable micelle solution administered IM with the efficacy of the same drug in an oral paste formulation. Parasite infections were naturally acquired in southern Louisiana. The drug was tested in both formulations at a dosage level of 0.2 mg/kg of body weight. Ivermectin in both formulations tested had an efficacy greater than 98% against Gasterophilus intestinalis and G nasalis larvae. Trichostrongylus axei, Habronema spp, Strongylus vulgaris, S. edentatus, and speci...
Davis JL, Papich MG, Morton AJ, Gayle J, Blikslager AT, Campbell NB.The purpose of this study was to determine the pharmacokinetics of etodolac following oral and intravenous administration to six horses. Additionally, in vitro cyclooxygenase (COX) selectivity assays were performed using equine whole blood. Using a randomized two-way crossover design, horses were administered etodolac (20 mg/kg) orally or intravenously, with a minimum 3-week washout period. Plasma samples were collected after administration for analysis using high pressure liquid chromatography with ultraviolet detection. Following intravenous administration, etodolac had a mean plasma half-li...
Cayzer J, Hedderley D, Gray S.Lyophilised products from green-lipped mussel (Perna canaliculus[LPPC]) are used to orally treat horses with osteoarthritis (OA). However, no randomised, controlled or double-blinded studies on the efficacy of this treatment in horses have been reported to date. Objective: To investigate the effects of a unique LPPC (Biolane)(1) in improving clinical signs of OA in the fetlock. Methods: Data were analysed from 26 horses with primary fetlock lameness in a controlled, randomised and double-blinded, multi-centre clinical trial. The study design was a partial crossover with a washout period and co...
Liska DA, Akucewich LH, Marsella R, Maxwell LK, Barbara JE, Cole CA.To determine serum pharmacokinetics of pentoxifylline and its 5-hydroxyhexyl metabolite in horses after administration of a single IV dose and after single and multiple oral doses. Methods: 8 healthy adult horses. Methods: A crossover study design was used with a washout period of 6 days between treatments. Treatments were IV administration of a single dose of pentoxifylline (8.5 mg/kg) and oral administration of generic sustained-release pentoxifylline (10 mg/kg, q 12 h, for 8 days). Blood samples were collected 0, 1, 3, 6, 12, 20, 30, and 45 minutes and 1, 2, 4, 6, 8, and 12 hours after IV a...
Vyniarska A, Ziółkowski H, Madej-Śmiechowska H, Jaroszewski JJ.The aim of this study was to compare the pharmacokinetics of ivermectin and its antiparasitic activity in two horse breeds. Eight Hutsul and 14 Toric horses were administered ivermectin orally at a dose of 0.2 mg/kg body weight. Blood samples were collected for 96 hr, and faecal samples were collected one day before and on days 14 and 21 after drug administration. Ivermectin concentrations in plasma samples were determined by high-performance liquid chromatography. Ivermectin concentration was significantly higher in Toric than in Hutsul horses 90 min after ivermectin administration and was...
Cutler C, Viljanto M, Hincks P, Habershon-Butcher J, Muir T, Biddle S.LGD-4033 is one of a number of selective androgen receptor modulators (SARMs) that are being developed by the pharmaceutical industry to provide the therapeutic benefits of anabolic androgenic steroids, without the less desirable side effects. Though not available therapeutically, SARMs are available for purchase online as supplement products. The potential for performance enhancing effects associated with these products makes them a significant concern with regards to doping control in sports. The purpose of this study was to investigate the metabolism of LGD-4033 in the horse following oral ...
Soma LR, Behrend E, Rudy J, Sweeney RW.The disposition of flunixin meglumine administered IV at a dosage of 1.1 mg/kg was described by a 2-compartment model; the alpha and beta half-lives (t1/2) were 0.61 and 1.5 hours, respectively. When administered IV at a rate of 2.2 mg/kg, the disposition was best described by a 3-compartment model, and the alpha, beta, and lambda t1/2 were 0.16, 1.52, and 6.00 hours, respectively. The zero-time plasma concentrations after flunixin meglumine was administered at 1.1 and 2.2 mg/kg were 9.3 +/- 0.76 and 21.5 +/- 7.4 mg/L, respectively. The bioavailability after oral administration of 1.1 mg/kg wa...
Donnell JR, Frisbie DD.This review presents the pathogenesis and medical treatment of equine osteoarthritis (OA), focusing on firocoxib. Inhibition of prostaglandin E remains a fundamental treatment for decreasing clinical symptoms (ie, pain and lameness) associated with OA in horses. Nonsteroidal anti-inflammatory drugs (NSAIDs), which inhibit the production of prostaglandin E from the arachidonic acid pathway, continue to be a mainstay for the clinical treatment of OA. Firocoxib is a cyclooxygenase (COX)-2-preferential NSAID that has been shown to be safe and to have a 70% oral bioavailability in the horse. Three ...
Doucet MY, Vrins AA, Dionne R, Alva R, Ericsson G.The efficacy of a paste formulation of the H+, K+, -ATPase inhibitor omeprazole was evaluated in standardbred racehorses for the treatment and prevention of gastric ulcers. Twenty standardbred racehorses in training, aged 2 to 9 years, were enrolled from 2 training centres in this field trial. Endoscopic examinations confirmed the presence of gastric ulcers in all horses, prior to allocation and treatment and on day 0. Lesions were scored on a scale of 0 to 3 (intact epithelium to extensive ulceration). Replicates were formed, based on training level and location. Within replicates, 1 horse wa...
Eby G.Arthritis is inflammation in a joint often with joint damage, usually accompanied by pain, swelling and stiffness, resulting from infection, trauma, degenerative changes, metabolic disturbances, autoimmune or other causes. It occurs in various forms, including rheumatoid arthritis, osteoarthritis, bacterial arthritis and gout. Gallium III can inhibit the production of inflammatory cytokines, such as IL-1beta, produced by macrophage-like cells in vitro. A dose-dependent inhibition of IL-1beta and TPA stimulated MMP activity by gallium nitrate at increasing concentrations occurs, demonstrating t...
Slocombe JO, Cote JF.Thirteen Standardbred horses, two to five years of age, were treated with ivermectin paste per os at 200 mug/kg of body weight and 13 were untreated. Two weeks after treatment, previously untreated horses were given the paste. Fecal samples were collected from all horses at the time of treatment and periodically thereafter up to 14 weeks and were examined for nematode eggs using the Cornell-McMaster dilution and the Cornell-Wisconsin double centrifugation procedures.All horses consumed the paste readily and had no signs of toxicosis. Strongyle eggs were found in the feces of all horses before ...
Klei TR, Torbert BJ, Chapman MR, Turk MA.A controlled test method was used to evaluate the efficacy of injectable micelle and oral paste formulations of ivermectin (22,23-dihydroavermectin B1) against 8-week-old Strongylus vulgaris larvae in experimentally infected pony foals. The dosage level of the drug in both formulations tested was 0.2 mg/kg. Ponies were euthanatized and necropsied 5 weeks after treatment. Based on the recovery of live vs dead S vulgaris from mesenteric arteries, both formulations were greater than 99% effective. Increased weight gains and marked reductions in the severity of arterial lesions were observed in tr...
Horspool LJ, McKellar QA.The present study was designed to determine and compare the plasma disposition and pharmacokinetics of penicillin G sodium following intravenous (i.v.) administration to horses, ponies and donkeys. The plasma disposition and pharmacokinetics of penicillin G was similar in horses, ponies and donkeys (elimination half-lives--39.0, 27.3 and 31.5 min, respectively) and a dosage interval of 6-8 h would be suitable to treat infections caused by susceptible bacteria. Although penicillin G was absorbed rapidly following nasogastric administration, the systemic availability was low (0.12-0.34%), theref...
Törneke K, Ingvast-Larsson C, Pettersson K, Bergvall K, Hedeland M, Bondesson U, Broström H.Clemastine is an H1 antagonist used in certain allergic disorders in humans and tentatively also in horses, although the pharmacology of the drug in this species has not yet been investigated. In the present study we determined basic pharmacokinetic parameters and compared the effect of the drug measured as inhibition of histamine-induced cutaneous wheal formation in six horses. The most prominent feature of drug disposition after intravenous dose of 50 microg/kg bw was a very rapid initial decline in plasma concentration, followed by a terminal phase with a half-life of 5.4 h. The volume of d...
Steinman A, Gips M, Lavy E, Sinay I, Soback S.Metronidazole pharmacokinetics in horses was studied after intravenous (i.v.), rectal (p.r.) and oral (p.o.) administration at 20 mg/kg using a triple crossover study design. Metronidazole mean+/-SD half-life was 196+/-39, 212+/-30 and 240+/-65 min after i.v., p.r. and p.o. administration, respectively. The metronidazole clearance was 2.8 (mL/min/kg) and the volume of distribution at steady state was 0.68 L/kg. The pharmacokinetic parameters calculated for metronidazole after administration of the drug by the various routes showed that bioavailability (74+/-18 vs. 30+/-9%) and maximum serum co...
Subhahar MB, Singh J, Albert PH, Kadry AM.Celecoxib, a nonsteroidal anti-inflammatory drug, is frequently used to treat arthritis in humans with minimal gastrointestinal side effect compared to traditional NSAIDs. The primary aim of this study was to determine the pharmacokinetic profile of celecoxib-a selective cyclooxygenase-2 (COX-2) inhibitor in horses. Six horses were administered a single oral dose of celecoxib at 2 mg/kg (body weight). After oral dosing, the drug reached a maximum concentration (mean ± SD) in blood of 1,088 ± 324 ng/ml in 4.58 hr. The elimination half-life was 13.60 ± 3.18 hr, and the area under th...
Moore I, Horney B, Day K, Lofstedt J, Cribb AE.The effect of oral treatment with natural or recombinant human interferon alpha (HIA) on inflammatory airway disease in young standardbreds was assessed in a double-blind, randomized clinical trial. A total of 34 horses with nasal discharge, excess mucus in the trachea, and a persistent cough of at least 2 weeks' duration that interfered with training completed the trial. Horses were rested for 1 week and received oral treatment with either a saline placebo, recombinant human interferon alpha (rHIA; 90 U/horse/day), or natural human interferon alpha (nHIA: 50 U/horse/day) for 5 days. There was...
Ferrucci F, Zucca E, Croci C, Di Fabio V, Ferro E.The severity of the erosive and ulcerative lesions of the squamous gastric mucosa in 10 standardbred racehorses in training was classified according to a standard scoring system. Each horse was then treated orally for 30 days with 50 g/100 kg bodyweight daily of a pectin-lecithin complex mixed into the feed. At the end of the period of treatment, the gastric lesions were re-evaluated gastroscopically and the scores were compared with those assigned at the previous evaluation. In three of the horses the gastric ulcerations had healed completely, and in six others the lesions had improved signif...
L'Ami JJ, Vermunt LE, van Loon JP, Sloet van Oldruitenborgh-Oosterbaan MM.A single dose of 40 μg/kg bodyweight (BW) of oromucosal detomidine gel was administered sublingually to 10 healthy Dutch Warmblood mares aged 7 ± 4 years (mean ± SD) and BW 580 ± 69 kg. Blood and urine samples were collected before and for 8 days following administration and evaluated qualitatively in an FEI Reference Laboratory and quantitatively in a research laboratory. Clinical effects were evaluated at baseline and for 24 h after administration. Sedation was determined using head height and scores of reaction to auditory and mixed auditory/sensory stimuli. Mechanical nociceptive thres...
Moore BR.Interferons are efficacious therapeutic agents for treatment of several clinically important diseases in cattle and horses. In some instances, the therapeutic goal of IFN administration is prevention or clinical cure of acute viral infections. On the other hand, IFN may serve as adjunctive treatment to diminish clinical manifestations of disease and improve the quality of life. Oral administration of IFN alpha appears to be a safe and convenient route of administration, and the therapeutic benefit likely develops via unique mechanisms involving oropharyngeal-associated lymphoid tissue for diss...
Bouckaert S, Voorspoels J, Vandenbossche G, Deprez P, Remon JP.Quinidine is the drug of choice for the treatment of cardiac arrhythmias in horses. The plasma concentrations vs. time profiles following oral administration of two formulations of quinidine sulphate, an oral solution and an oral suspension paste, were evaluated in nine horses. They received multiple administrations of the oral solution under fed and non-fed conditions and of the paste under non-fed conditions. A loading dose of 20 mg.kg-1 and a maintenance dose of 10 mg.kg-1 quinidine with dosing interval of 6 h were used. The relative bioavailability of the oral solution under fed conditions...
Perdrizet JA, Scott DW.Cellulitis and subcutaneous abscess formation was diagnosed in a 3-month-old Thoroughbred filly. Clinical signs consisted of a large ulcerated plaque, with satellite pustules on the medial aspect of the right hock and subcutaneous abscesses in the right inguinal and mammary gland areas. Laboratory analysis revealed mature neutrophilia. Rhodococcus equi was isolated from the cellulitis and the subcutaneous abscess. Oral administration of erythromycin and rifampin for 35 days resulted in a clinical cure.
Pompa G, Caloni F, Montana M, Pasqualucci C.1. Isoxsuprine [1-(4-hydroxyphenyl)-2-(1-methyl-2-phenoxyethylamino)-1- propanol] serum concentrations after single- and multiple-dose administration to horse were investigated using immunoenzymatic ELISA, HPLC-UV and thermospray HPLC-MS methods. 2. Using HPLC-MS, isoxsuprine was detected up to 72 h after a single administration (1.2 mg/kg by gastric probe) and up to 96 h after the end of serial administration (1.2 mg/kg every 12 h for 7 days). 3. ELISA detected the drug up to 96 h after a single dose and up to 6 days after the end of prolonged administration. 4. Isoxsuprine is present in hors...
Owen JM.Thirty eight cases of Fasciola hepatica infection in horses with associated clinical signs are reported. A method of examining large amounts of faeces for fluke is described. A safe method of treatment for infected horses is given which involves oral medication with oxyclozanide at a dose rate of 15 ml/50 kg body weight.
Davis JL, Papich MG, Weingarten A.The purpose of this study was to determine the pharmacokinetics and physicochemical characteristics of orbifloxacin in the horse. Six healthy adult horses were administered oral and intravenous orbifloxacin at a dose of 2.5 mg/kg. Plasma samples were collected and analyzed by high-pressure liquid chromatography with ultraviolet detection. Plasma protein binding and lipophilicity were determined in vitro. Following i.v. administration, orbifloxacin had a terminal half-life (t1/2) of 5.08 h and a volume of distribution (V(d(SS))) of 1.58 L/kg. Following oral administration, the average maximum p...
