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.
Plasma and Urinary Elimination Profiles of Medetomidine Metabolites in Horses for the Purpose of Doping and Medication Control. Medetomidine, an α₂-adrenergic agonist, is widely used as a sedative in horses. While its pharmacological effects are established, limited data exist on elimination of its metabolites, 3'-hydroxy medetomidine (HMD) and 3'-carboxy medetomidine (CMD), which are of regulatory interest. HMD is currently targeted in plasma and urine under International Screening Limits (ISLs) established by the International Federation of Horseracing Authorities (IFHA). In this study, seven Thoroughbreds received 6.3 μg/kg of medetomidine intravenously. Blood and urine were collected for 96 h and analyzed b...
Obtention and preliminary clinical evaluation of an equine albumin for intravenous administration in adult Colombian Creole Horses (Equus ferus caballus). Albumin is one of the most abundant and physiologically important blood protein in horses due to its ability to regulate vascular volume and transport blood metabolites or drugs. Despite the importance of this protein, in Colombia there is no previous reference of the use of equine albumin in horses as a pharmacological therapy and there is no available any pharmaceutical preparation of this protein to be administrated in horses. This study aims to evaluate for first time the preliminary clinical response of healthy adult Colombian Creole horses after the intravenous administration of an equin...
Comparison of two doses of lidocaine constant rate infusion on cardiopulmonary function and recovery in isoflurane-anesthetized horses. To compare cardiopulmonary variables and recovery scores in isoflurane-anesthetized horses undergoing arthroscopy using two different intravenous (IV) lidocaine constant rate infusions (CRIs; 50 or 100 μg kg minute) under intermittent positive pressure ventilation (IPPV) or spontaneous ventilation (SV). Methods: Prospective, randomized, clinical study. Methods: A group of 30 client-owned horses, 8-156 months old (range), with body masses of 280-550 kg. Methods: Anesthesia protocol consisted of xylazine, ketamine and diazepam, and maintenance with isoflurane and a CRI of dexmedetomidine. All g...
Pharmacokinetics and Anti-Inflammatory Effects of Intramuscular Betamethasone in Exercised Thoroughbred Horses. The pharmacokinetics and pharmacodynamics of betamethasone following intra-articular administration to horses have been described; however, studies characterizing intramuscular administration are lacking. Twenty-four horses received an intramuscular dose of 12 mg betamethasone sodium phosphate/betamethasone acetate. Blood and urine were collected at post administration for up to 408 h. Concentrations of betamethasone were determined using LC-MS/MS and pharmacokinetic parameters determined using a Population PK three-compartment model. The duration of pharmacodynamic effects was assessed by...
Survey describing the perspectives and practices of Australian veterinarians to pain management in horses. To describe Australian practices and attitudes regarding equine analgesia. Methods: Cross-sectional anonymous, voluntary survey of Australian veterinarians treating equine patients. Methods: Australian veterinarians in equine or mixed practices completed a six-section, 60-question survey between November 2019 to August 2020. Information was gathered on demographics, analgesia prescription, pain assessment and attitudes surrounding specific analgesics. Respondents assigned a pain score ranging from 0 to 10 for various conditions; these were averaged to give each respondent an "average pain scor...
Exposure to Subcutaneously Administered Butorphanol in Horses Pre-Treated With Detomidine or Detomidine-Vatinoxan. The aim of the study was to determine the exposure to subcutaneously administered butorphanol in horses pre-treated with intravenous (IV) detomidine, with or without vatinoxan, a peripherally selective alpha-adrenoceptor antagonist. Five healthy, adult horses received three IV treatments 7 days apart, in a randomized, cross-over design: detomidine 20 μg/kg (DET-B), detomidine 20 μg/kg with vatinoxan 200 μg/kg (DETVAT-B) and saline (S-B), all followed by 0.1 mg/kg of butorphanol administered subcutaneously 30 min later. Venous samples were collected between 10 and 270 min after...
Successful Treatment of Cutaneous Lupus Erythematosus in a Horse With Tacrolimus Ointment. A 9-year-old gelding Quarter Horse with a lesion on the right upper eyelid was diagnosed with cutaneous lupus erythematosus. Clinical resolution and control of UV-induced flares were achieved with topical tacrolimus and a UV-blocking mask without adverse effects over the following 3 years.
Case Report: Inhaled salbutamol in the successful treatment of life-threatening acute hyperkalaemia in an anaesthetised horse. Hyperkalaemia is an uncommon complication of general anaesthesia in healthy horses. This case report describes the occurrence of life-threatening acute hyperkalaemia in a 13-year-old, female French Trotter anaesthetised for experimental right and left atrial 3D electro-anatomical mapping. Intra-operative development of hyperkalaemia (7.55 mmol/L) (Ref. 3.00-4.00 mmol/L) with atrial standstill on ECG necessitated transvenous ventricular pacing while initial treatment with insulin and glucose was initiated. Plasma potassium levels continued to increase (8.00 mmol/L) prompting adjunctive tr...
Vonoprazan pharmacokinetics and effects on gastric pH following administration to fed and fasted horses. Current treatment options for equine gastric ulcer syndrome (EGUS), such as omeprazole-a proton pump inhibitor (PPI)-have notable limitations, including the need for administration on an empty stomach. Potassium-competitive acid blockers (P-CABs), such as vonoprazan, are a newer class of acid suppressants that offer several advantages over PPIs in humans and may provide similar benefits in horses. Objective: To describe the pharmacokinetics and effect of a single oral dose of vonoprazan on intragastric pH in horses. We hypothesised that vonoprazan would follow linear kinetics across the doses ...
Enrofloxacin induces mild and transient vascular alterations following regional limb perfusion in horses. Regional intravenous limb perfusion (RILP) is widely used in equine practice for achieving high local antimicrobial concentrations while minimizing systemic exposure. However, certain drugs, including enrofloxacin, have been associated with vascular irritation and thrombosis, and their thrombogenic potential remains poorly characterized. Objective: This study aimed to evaluate the thrombogenic potential of enrofloxacin administered via RILP in the cephalic vein of clinically healthy horses. Methods: Ten adult horses underwent RILP in both forelimbs: the right limb received 10 % enrofloxacin (1...
Efficacy of Ozone Bagging Therapy in Equine Chronic Distal Limb Wounds: Clinical Evaluation of Eight Cases. Limb wounds in horses represent a significant therapeutic challenge due to poor vascularization, reduced skin elasticity, and high risk of complications such as exuberant granulation tissue. Conventional treatments sometimes fail to provide satisfactory healing outcomes, leading to prolonged recovery and increased costs. This study aimed to evaluate the efficacy of topical ozone therapy using the bagging method in promoting the epithelialization and contraction of chronic distal limb wounds in horses refractory to conventional management. Eight horses, aged 3-21 years, with chronic wounds aver...
Videofluoroscopy shows clinically relevant changes in swallow metrics and esophageal transit in normal horses with xylazine, anticholinergic use, and varied feed consistency. To investigate the effects of varied feed consistency and administration of xylazine or N-butylscopolammonium bromide on 3 phases of swallowing and characterize esophageal motility following barium administration via nasoesophageal tube. Unassigned: 8 healthy horses were enrolled for 2.5 consecutive weeks. Horses underwent experimental videofluoroscopic swallow studies before and after sedated and anticholinergic interventions. Esophageal motility was assessed with barium administered via nasoesophageal tube and with barium-admixed feedstuffs of 3 consistencies with increasing viscosity. Phase...
Clinical features, diagnostic findings, and treatment response in Finnish horses examined for equine inflammatory bowel disease. Equine inflammatory bowel disease (IBD) is challenging to diagnose and treat. Although the number of horses examined due to suspicion of IBD is increasing, the different treatments in clinical patients and their responses are not well documented. We sought to characterize the demography, signs, clinical and rectal biopsy findings, and treatment response in Finnish horses suspected to have IBD. Horses undergoing clinical examination due to suspected IBD in 2022 and with a good-quality rectal biopsy were selected for the study. General information, signs, clinical and histological findings, and ...
Dexmedetomidine Prolongs the Duration of Ropivacaine Corneal Anesthesia After Subconjunctival Injection in Healthy Horses. To determine whether dexmedetomidine prolongs corneal anesthesia following subconjunctival ropivacaine injection in healthy equine eyes. Methods: Ten horses with normal ophthalmic exams were enrolled in a randomized, blinded, crossover experiment with a minimum 4-week washout between treatments. Baseline corneal touch thresholds (CTT, cm) were measured via esthesiometry and a subconjunctival injection was performed in the treatment eye with ropivacaine (R, 0.3 mL 0.5%) or dexmedetomidine-ropivacaine (DR, 0.1 mL 0.5 mg/mL + 0.2 mL 0.5%) and saline (control, 0.3 mL) in the contrala...
Oral administration of pimobendan in healthy horses results in low plasma concentrations. To describe the pharmacokinetics of a single dose of pimobendan (Vetmedin) in healthy adult horses and provide preliminary evidence of the absorption of 2 compounded pimobendan formulations. Unassigned: From August 2022 through November 2022, 6 healthy adult horses were administered a single dose of 0.5 mg/kg pimobendan orally. A subset of 2 horses was also administered pimobendan, compounded as an oil-based suspension and a capsule formulation. Plasma was collected at times 0, 15, 30, and 45 minutes and 1, 2, 4, 8, 12, and 24 hours after administration. The plasma concentrations of pimobendan...
Liposomal bupivacaine caudal epidural in horses results in adverse effects without analgesia. To evaluate the analgesic properties and adverse effects of liposomal bupivacaine administered via caudal epidural in horses. Methods: Pharmacodynamic study. Methods: A total of 10 healthy adult horses. Methods: Liposomal bupivacaine (10 mL; 1.3%) was administered into the caudal epidural space via an indwelling epidural catheter inserted to a length of 15 cm. Mechanical nociceptive threshold (MNT) testing with pressure algometry was used to measure analgesia at four anatomic locations for 72 h following injection. Physical examinations (including rectal temperature, heart rate, respirat...
Metformin in the Horse: Pharmacokinetics and Detection Times Using Monte Carlo Simulations. The racehorse industry has strict regulations regarding the detection of prohibited substances in horses. Metformin, a diabetes medication, is a prohibited substance that has been reported in post-race blood and urine samples collected from racehorses. For further characterization of the disposition of metformin, 12 Thoroughbred horses were administered metformin orally and intravenously in a randomized, balanced, two-way crossover design. Serum and urine samples were collected, and drug concentrations determined via liquid chromatography-tandem mass spectrometry. The serum data were analyzed ...
Effects of Lidocaine Alone Versus Lidocaine-Dexmedetomidine Infusion on Pulmonary Gas Exchange and Respiratory Mechanics During Isoflurane Anesthesia in Horses. Dexmedetomidine improves pulmonary function in dogs and humans, but evidence in horses is scarce. This study evaluated dexmedetomidine infusion on oxygenation and respiratory mechanics in anesthetized horses. Twenty horses undergoing elective surgery were included in a prospective, non-randomized, observational study. Horses received either lidocaine alone (1.3 mg/kg over 15 min, then 3 mg/kg/hour; LIDO) or combined with dexmedetomidine (1.75 μg/kg over 15 min, then 1.75 μg/kg/hour; DL). Respiratory mechanics, gas exchange, and cardiovascular variables were recorded at baseline, post-loading...
A Meta-Analysis of International Flunixin Pharmacokinetics in Horses: Toward Regulatory Harmonization and Individualized Detection Times Using Bayesian Paradigm. Flunixin meglumine is widely used to manage pain and inflammation in horses, and its regulation requires robust pharmacokinetic analysis for harmonization. In this study, we conducted a meta-analysis of flunixin disposition using plasma and urine concentration data from 65 horses across four countries to robustly estimate pharmacokinetic parameters in setting screening limits (SLs) for controlling medications in horses. A population (POP) model was developed using nonlinear mixed-effects model analysis. The irrelevant plasma concentration (IPC) and irrelevant urine concentration (IUC) were det...
Effect of N-Butylscopolammonium Bromide and Metamizol Sodium on Heart Rate, Blood Pressure, and Echocardiographic Measurements in Warmblood Horses With Aortic and Mitral Valve Regurgitation. Administration of N-butylscopolammonium bromide (NBB) with metamizol sodium (NBBM) causes tachycardia and hypertension, and has been associated with accentuated cardiac murmurs. Objective: To evaluate the effect of a pharmacological challenge using NBBM on valvular regurgitation and cardiac murmurs in horses with aortic (AR) and mitral valve regurgitation (MR). Methods: Twenty Warmblood horses with AR and 20 with MR. Methods: Cardiac auscultation and two-dimensional (2D), M-mode, color flow, pulsed wave Doppler flow, and tissue Doppler echocardiography were performed with simultaneous ECG reco...
Plasma and Urine Pharmacokinetics of Intravenous Pridinol in Thoroughbreds for Its Medication Control. We examined the pharmacokinetics of intravenous pridinol in six thoroughbred horses. Each horse received a single 20 mg dose of pridinol mesylate via the jugular vein, and plasma and urine samples were collected over 72 h. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to quantify pridinol concentrations in plasma and urine, allowing for the calculation of pharmacokinetic parameters. A three-compartment model best fit the plasma elimination data. Using the Toutain model, irrelevant plasma and urine concentrations were estimated to be 0.00284 and 0.000612 ng/mL, respec...
Adverse Effects of Antimicrobial Drugs Use in Horses. Antimicrobial drug therapy in horses can lead to adverse effects across multiple body systems, with specific age groups, such as foals, at particular risk. Certain antimicrobial drugs, such as penicillins, aminoglycosides, macrolides, tetracyclines, and trimethoprim-sulfonamide combinations, are commonly implicated. This review explores the mechanisms behind these adverse reactions, emphasizing the importance of judicious antimicrobial drug use. This review also underscores the need for a centralized pharmacovigilance system to improve drug safety and adverse event reporting for veterinary med...
Preanesthetic Administration of Trazodone Does Not Impact Anesthetic Recovery Scores in Horses. Trazodone is administered to hospitalized equine patients to aid in behavioral management, but the effects on the anesthetic recovery period have not been investigated. This study sought to determine if there is an association between trazodone administration and recovery quality, recovery time, need for sedation, or need for reversal agent administration. We hypothesized that there would be no difference in recovery scores, recovery time, additional sedation, or reversal agent administration between horses that received preanesthetic trazodone and horses that did not. Records were reviewed to...
Influence of Extended Photoperiod Using Blue Light Masks on Hypertrichosis, Coat Condition and General Health Parameters in Horses with Pituitary Pars Intermedia Dysfunction. Fifty-two horses aged >15 years, diagnosed with pituitary pars intermedia dysfunction (PPID), and displaying hypertrichosis were recruited via an online survey of PPID horse owners. From mid-December, group T ( = 29) wore Equilume light masks extending photoperiod to 15 h daily, while group C1 ( = 23) remained under natural photoperiod. As 85% (44/52) of recruited study horses received pergolide medication, a second unmedicated PPID research herd (C2; = 17) was recruited and remained under natural photoperiod. Hair coat samples, shedding and body condition scores were collected monthly by own...
Intravenous clomiphene citrate pharmacokinetics in healthy mares as a first step toward use in reproduction. To investigate the IV pharmacokinetic parameters of clomiphene citrate (CC), a selective estrogen receptor modulator, in mares. Unassigned: This was an experimental study to assess the pharmacokinetic parameters of CC in the mare. Eight mares received a single 2,000-mg dose of IV CC to identify plasma concentrations over 336 hours. Following this, 6 mares received a multidose regimen of IV CC (2,000 mg, q 24 h) for 5 days to identify trough plasma concentration each day. Unassigned: CC was well tolerated, demonstrated a short elimination half-life of 4.95 ± 1.10 hours and a mean residence tim...
Adverse Effects and Drug Reactions in Equids. Adverse drug events (ADEs) are any harms caused by medical interventions used for treatment, prevention, or diagnosis. These events can happen due to human error or as unintended, harmful reactions to drugs when given at normal therapeutic doses. This review focuses on common ADEs associated with drugs frequently used in equine practice. Recognizing and understanding the manifestations of ADEs can help with early detection and more effective management, ultimately leading to better outcomes for equine patients. Additionally, knowledge of the potential harmful effects of drugs also aids in appr...
Retrospective Assessment of Carbonic Anhydrase Inhibitors in Topical or Episcleral Implant Form for the Treatment of Equine Glaucoma. To assess whether topical carbonic anhydrase inhibitors (CAIs) with or without episcleral brinzolamide implants control intraocular pressure (IOP) in horses with glaucoma. Methods: 12 client-owned horses diagnosed with glaucoma. Methods: Medical records of horses treated with topical CAIs for ≥ 14 days, with a subset receiving episcleral brinzolamide implants, were reviewed. Diagnosis, signalment, concurrent ocular disease, medications, IOP, visual status, and additional procedures were recorded. Treatment failure was defined as horses with IOP > 30 mmHg resulting in phthisis bulbi o...
Antibiotic Use in Horses: Analysis of 57 German Veterinary Practices (2018-2023). : A mandatory monitoring of the use of antibiotics in horses in the European Union will come into force from 2027 on. The aim of the study was to explore the potential implementation of a monitoring system and to provide an overview of antibiotic use in horses in Germany. : Data on all consultations from 57 German practices between 2018 and 2023 were obtained. The dataset included basic data about the horse, free-text diagnoses (allocated to one of 20 categories), and treatments. Information on the administered or dispensed pharmaceutical product was recorded for antibiotic treatment consultat...
Misconceptions and misuse: assessing horse caregivers’ knowledge, attitudes, and practices regarding dexamethasone use in Ibadan, Nigeria. Dexamethasone is a common drug used in equine medicine, but when administered inappropriately, it can lead to serious health complications. There is a dearth of data on horse caregivers' knowledge, attitudes, and practices regarding dexamethasone use in Nigeria. Understanding current dexamethasone usage patterns is necessary for developing educational interventions which will then improve equine welfare. This study aimed to assess the knowledge, attitudes, and practices (KAP) of horse caregivers regarding dexamethasone use in Ibadan, Nigeria. A cross-sectional study was conducted amongst a tot...
Development and validation of general urine screening method for performance enhancing drugs in racehorses utilizing liquid chromatography-high resolution mass spectrometry (LC-HRMS). The complexity of the drug market and the constant updating of drugs have been challenging issues for drug regulatory authorities. In this manuscript, a high-throughput automated assay based on Liquid Chromatography High Resolution Mass Spectrometry (LC-HRMS) suitable for use as an initial testing procedure covering multiple classes of compounds prohibited in horse racing is described. The assay requires a 250-μL urine aliquot, which is subjected to enzymatic hydrolysis followed by Biotage Isolute supported liquid extraction plates using Biotage Extrahera system, evaporation, and reconstituti...