Topic:Medication
The topic of medication in horses encompasses the study and application of pharmaceutical substances used to treat, manage, or prevent diseases and conditions in equine patients. This field involves understanding the pharmacokinetics and pharmacodynamics of various drugs, including their absorption, distribution, metabolism, and excretion in horses. Medications commonly administered to horses include non-steroidal anti-inflammatory drugs (NSAIDs), antibiotics, anthelmintics, and sedatives. The appropriate use of these medications is critical for ensuring therapeutic efficacy and minimizing adverse effects. Research in this area focuses on dosage optimization, drug interactions, resistance development, and withdrawal times to ensure both the health of the horse and compliance with regulatory standards. This page aggregates peer-reviewed studies and scholarly articles that explore the pharmacological aspects, clinical applications, and regulatory considerations of equine medications.
Efficacy of omeprazole powder paste or enteric-coated formulation in healing of gastric ulcers in horses. GastroGard, an omeprazole powder paste formulation, is considered the standard treatment for gastric ulcers in horses and is highly effective. Gastrozol, an enteric-coated omeprazole formulation for horses, has recently become available, but efficacy data are controversial and sparse. Objective: To investigate the efficacy of GastroGard and Gastrozol at labeled doses (4 and 1 mg of omeprazole per kg bwt, respectively, PO q24h) in healing of gastric ulcers. Methods: 40 horses; 9.5 ± 4.6 years; 491 ± 135 kg. Methods: Prospective, randomized, blinded study. Horses with an ulcer score ≥1 (Equi...
Controlled nail delivery of a novel lipophilic antifungal agent using various modern drug carrier systems as well as in vitro and ex vivo model systems. The penetration behavior into human nails and animal hoof membranes of a novel antifungal agent (EV-086K) for the treatment of onychomycosis was investigated in this study. The new drug provides a high lipophilicity which is adverse for penetration into nails. Therefore, four different formulations were developed, with particular focus on a colloidal carrier system (CCS) due to its penetration enhancing properties. On the one hand, ex vivo penetration experiments on human nails were performed. Afterwards the human nail plates were cut by cryomicrotome in order to quantify the drug concentratio...
Detection and pharmacokinetics of three formulations of firocoxib following multiple administrations to horses. The use of firocoxib in horses and its ability to affect performance and potential to allow a horse to compete when it otherwise should not, necessitates establishing appropriate withdrawal time guidelines prior to performance. Objective: To describe plasma concentrations and characterise the pharmacokinetics of 3 firocoxib formulations following multiple administrations of the label dose, with respect to recommended plasma thresholds for performance horses. Methods: Balanced 3-way crossover prospective study. Methods: Nine healthy mature horses were administered firocoxib injectable solution ...
Use of lomustine (CCNU) in a case of cutaneous equine lymphoma. A 12-year-old gelding was diagnosed with recurrent lymphoma in multiple cutaneous sites. A highly invasive preputial mass caused urethral obstruction. The horse was treated with surgery and chemotherapy consisting of lomustine (CCNU) and prednisolone. The treatment was well-tolerated and effective. This is the first reported use of lomustine (CCNU) in a horse for the treatment of equine lymphoma. Utilisation de lomustine (CCNU) dans un cas de lymphone cutané équin. Un hongre âgé de 12 ans a été diagnostiqué avec un lymphome récurrent sur plusieurs sites cutanés. Une masse préputiale ...
Disposition of firocoxib in equine plasma after an oral loading dose and a multiple dose regimen. The objective of this study was to determine if a single loading dose (LD), 3× the label dose of firocoxib oral paste, followed by nine maintenance doses at the current label dose achieves and maintains near steady state concentrations. Six healthy, adult mares were administered 0.3mg/kg of firocoxib on Day 0, and 0.1 mg/kg 24 h later on Day 1, and at 24 h intervals from Day 2 to Day 9, for a total of 10 doses. Blood samples were collected throughout the study. The mean firocoxib maximum plasma concentration and standard deviation was 199±97 ng/mL, 175±44 ng/mL and 183±50 ng/mL after the L...
Indenopyride derivative RTI-4587-073(l): a candidate for male contraception in stallions. The objective of this study was to determine whether an indenopyridine derivative RTI-4587-073(l) was a good candidate for male contraception in horses. We hypothesized that a single administration of RTI-4587-073(l) causes significant suppression of testicular function in stallions without affecting sexual behavior. Three Miniature horse stallions received a single dose of 12.5 mg/kg RTI-4587-073(l) orally (group "treated"), whereas three other Miniature horse stallions received placebo only (group "control"). Semen was collected and evaluated from all stallions twice a week for three baselin...
A clinician’s guide to factors affecting withdrawal times for equine therapeutic medications. Equine forensic science can now detect concentrations down to 25 femtograms/mL (parts per quadrillion, ppq) or less in blood and urine. As such, horsemen are increasingly at risk of inadvertent 'positives' due to therapeutic medication 'overages' or trace identifications of dietary or environmental substances. Reviewed here are the factors which determine detection times and 'withdrawal times' for substances administered to horses. Withdrawal times are affected by many factors, including dose, formulation, route and frequency of administration, bioavailability, plasma half-life, sensitivity of...
The pharmacokinetics of methocarbamol and guaifenesin after single intravenous and multiple-dose oral administration of methocarbamol in the horse. A simple LC/MSMS method has been developed and fully validated to determine concentrations and characterize the concentration vs. time course of methocarbamol (MCBL) and guaifenesin (GGE) in plasma after a single intravenous dose and multiple oral dose administrations of MCBL to conditioned Thoroughbred horses. The plasma concentration-time profiles for MCBL after a single intravenous dose of 15 mg/kg of MCBL were best described by a three-compartment model. Mean extrapolated peak (C0 ) plasma concentrations were 23.2 (± 5.93) μg/mL. Terminal half-life, volume of distribution at steady-state...
Risk of septic arthritis after intra-articular medication: a study of 16,624 injections in Thoroughbred racehorses. The aims of this study were to determine the risk of septic arthritis after intra-articular medication (IAM) and to identify potential risk factors for this complication. Methods: A retrospective and prospective descriptive study of prevalence, and matched case-control study for risk factors. Results: Of 16,624 joints injected in 1103 horses at 6695 horse-visits, septic arthritis occurred as a complication in 13 joints (13 horses). The risk of septic arthritis following IAM was 7.8 cases per 10,000 injections or 1 case per 1279 injections. Veterinarian and type of corticosteroid were identifie...
Postcastration analgesia in ponies using buprenorphine hydrochloride. Buprenorphine has recently obtained UK Marketing Authorisation for horses. The analgesic effects are long lasting, and have considerable potential for postoperative pain relief. This observer blinded, randomised study aimed to evaluate postsurgical analgesia in ponies premedicated with buprenorphine prior to castration under intravenous anaesthesia. Ponies received either 0.01 mg/kg bodyweight (BW) buprenorphine (group B) or an equivalent volume of 5 per cent glucose (group C) given intravenously before induction of anaesthesia. Pain was assessed and recorded using dynamic interactive visual a...
Pharmacokinetics of a peroral single dose of two long-acting formulations and an aqueous formulation of doxycycline hyclate in horses. Doxycyline (Dox) is a semisynthetic antibacterial drug with pharmacological advantages over its parent drug (tetracycline) in the treatment of various bacterial diseases in horses. Yet, at present a horse-customized pharmaceutical formulation is not available. Based on its pharmacokinetic/pharmacodynamic (PK/PD) ratio, Dox is considered a time-dependent antibacterial drug and ideally expected to achieve sustained plasma drug concentrations both at or slightly above the minimal inhibitory concentration (MIC) level for as long as possible between dosing intervals. Hence, the objective of this st...
Pharmacokinetics and safety of oral administration of meloxicam to foals. The pharmacokinetics, efficacy, and safety of meloxicam have been evaluated in adult horses, but not foals. Physiologic differences between neonates and adults might alter drug pharmacokinetics and therapeutic index. Objective: The pharmacokinetics of meloxicam will be different in foals compared with adult horses, and foals could be at increased risk for adverse drug effects. Methods: Twenty lightbreed foals less than 6 weeks of age at commencement of the study. Methods: Single and repeated oral dose pharmacokinetics were determined for meloxicam (0.6 mg/kg) in 10 foals. The safety of the d...
Inhaled anesthetics in horses. Inhaled agents represent an important and useful class of drugs for equine anesthesia. This article reviews the ether-type anesthetics in contemporary use, their uptake and elimination, their mechanisms of action, and their desirable and undesirable effects in horses.
Pharmacokinetics and pharmacodynamic effects of tolazoline following intravenous administration to horses. Tolazoline is an α2-adrenergic receptor antagonist, used in veterinary medicine to antagonize the central nervous system depressant and cardiovascular effects of α2 receptor agonists. The pharmacokinetics and pharmacodynamic effects of tolazoline when administered subsequent to detomidine in the horse were recently reported, although the reversal of the sedative and cardiovascular effects following detomidine may not be complete. The current study therefore investigated the pharmacokinetics and pharmacodynamic effects of tolazoline when administered as a sole agent. Nine healthy adult horses...
Total intravenous anesthesia in horses. Total intravenous anesthesia (TIVA) is the mainstay of short-term (up to 60 minutes) and field anesthesia in horses. This article discusses the pros and cons of TIVA, commonly used TIVA protocols, and their use, monitoring during, and recovery from, TIVA.
Systemic or intrasynovial medication as singular or as combination treatment in horses with (peri-)synovial pain. Records of lame horses (2004-2007) with (peri-)synovial pain of the metacarpophalangeal joint (MCPJ, n = 53), digital flexor tendon sheath (DFTS, n = 20), and distal interphalangeal joint (DIPJ, n = 31) were evaluated (n = 104). Cases were grouped according to the following treatments: (1) systemic administration of NSAIDs (n = 40); (2) intrasynovial administration of glucocorticosteroids (n = 30); (3) combination treatment (n = 34). Outcome was defined as successful when the owner reported that the horse had returned to its previous level of performance within a period of up to six months aft...
Influence of exercise on the distribution of technetium Tc 99m medronate following intra-articular injection in horses. To determine the effects of exercise on the distribution and pharmacokinetics of technetium Tc 99m medronate ((99m)Tc-MDP) following intra-articular (IA) injection in horses. Methods: 5 horses. Methods: 1 antebrachiocarpal joint (ACJ)/horse was assigned to the exercised group (n = 5), and the contralateral ACJ was evaluated in the nonexercised group (5) after a minimum washout period of 7 days. Following IA injection of (99m)Tc-MDP (148 MBq), blood and scintigraphic images of the carpus were obtained at 5, 10, 15, 20, 25, 30, 45, 60, 90, 120, 240, 360, 480, 600, 720, and 1,440 minutes. Plasma ...
A nebulized gelatin nanoparticle-based CpG formulation is effective in immunotherapy of allergic horses. In the recent years, nanotechnology has boosted the development of potential drug delivery systems and material engineering on nanoscale basis in order to increase drug specificity and reduce side effects. A potential delivery system for immunostimulating agents such as cytosine-phosphate-guanine-oligodeoxynucleotides (CpG-ODN) needs to be developed to maximize the efficacy of immunotherapy against hypersensitivity. In this study, an aerosol formulation of biodegradable, biocompatible and nontoxic gelatin nanoparticle-bound CpG-ODN 2216 was used to treat equine recurrent airway obstruction in ...