Pharmacology in horses involves the study and application of drugs and medications to diagnose, treat, and prevent diseases and conditions in equine species. This field encompasses the understanding of pharmacokinetics and pharmacodynamics specific to horses, including how drugs are absorbed, distributed, metabolized, and excreted by the equine body. Commonly studied pharmacological agents in horses include non-steroidal anti-inflammatory drugs (NSAIDs), antibiotics, sedatives, and anthelmintics. Research in equine pharmacology focuses on determining appropriate dosages, understanding drug interactions, and minimizing adverse effects. This page compiles peer-reviewed research studies and scholarly articles that investigate the efficacy, safety, and regulatory aspects of pharmacological interventions in equine veterinary practice.
This article provides an overview of initial assessment and management of common emergency presentations in donkeys and mules. The principles are similar to those in horses (and ponies), but clinicians must be aware of differences in recognition of signs of pain/disease, approach to handling, pharmacology of some drugs, and subtle differences in the physiology and local anatomy in donkeys and mules. The epidemiology of common disease presentations will vary between pet/companion or working/farmed donkeys and mules. Regular dental checks, deworming, vaccination, and monitoring of behavior and q...
Fifteen horses harboring naturally acquired, patent Parascaris equorum and Oxyuris equi infections were equally allotted to 3 treatment groups given (1) injectable vehicle; (2) injectable ivermectin at the dose rate of 200 microgram/kg of body weight; and (3) injectable ivermectin at the rate of 300 microgram/kg. All treatments were given IM in the neck. All animals were killed 14 days after treatment and examined for the targeted nematodes. Regardless of dose rate, ivermectin proved 100% effective in the removal of adult O equi and P equorum infections. Levels of immature P equorum were decre...
The objective of this study was to compare effects of butorphanol (BUT) or buprenorphine (BUP), in combination with detomidine and diazepam, on the sedation quality, surgical conditions, and postoperative pain control after cheek tooth extraction in horses, randomly allocated to 2 treatment groups (BUT: = 20; BUP: = 20). A bolus of detomidine (15 μg/kg, IV) was followed by either BUP (7.5 μg/kg, IV) or BUT (0.05 mg/kg, IV). After 20 min, diazepam (0.01 mg/kg, IV) was administered and sedation was maintained with a detomidine IV infusion (20 μg/kg/h), with rate adjusted based on scores to ...
Guzmán JFC, Gontijo AS, Melgaço ES, Faria SA, Baldi MLC, Sousa LN, Wenceslau RR, Fantini P, Xavier ABDS, Beier SL.Morphine has significant clinical and analgesic effects in horses, but its impact on the gastrointestinal tract requires further understanding. This study assessed the analgesic and gastrointestinal effects of morphine in horses undergoing elective orchiectomy in the quadrupedal position. Thirty uncastrated male horses were randomly assigned to three groups: orchiectomy without morphine and sedation protocol (OSM), orchiectomy with morphine and sedation protocol (OM), and administration of morphine alone in the absence of orchiectomy (M). The anesthetic protocol involved acepromazine (0.05 mg/...
Júnior GS, de Souza JV, de Souza Ferreira W, Florentino VRD, Valente TC, Comassetto F, Oleskovicz N.This study aimed to evaluate the sedation degree, cardiopulmonary effects, and detomidine-sparing during dental occlusal adjustment in standing horses using a bolus and constant rate infusion (CRI) of detomidine alone or in combination with butorphanol or methadone. In this randomized, blinded clinical trial, 24 healthy adult horses were assigned to the detomidine (DT), detomidine-butorphanol (DB), or detomidine-methadone (DM) group. DT received an intravenous bolus of detomidine (20 μg/kg), followed by CRI at 20 μg/kg/h. DB received detomidine (10 μg/kg) and butorphanol (0.02 mg/kg) boluse...
Sheahan BJ, Schubert AG, Schubert W, Sheats MK, Schnabel LV, Gilbertie JM.Neutrophil extracellular traps (NETs) play a significant role in response to a variety of infectious and inflammatory stimuli in human and veterinary medicine. Although entrapment of bacteria can be an important function of NETs, the exuberant release of DNA and other intracellular molecules has also been negatively implicated in the pathogenesis of different diseases. Thus, NET formation must be tightly controlled and represents an opportunity for therapeutic interventions. Horses are particularly sensitive to bacterial stimuli that have previously been shown to cause NETs in other species, b...
Gorenberg EB, Slack J, Stefanovski D, Theiss D, Hopster K.Dobutamine is a first-line therapy for hypotension in anaesthetised horses, but the effects on haemodynamic parameters in standing and anaesthetised horses are not well studied. Objective: To investigate the effects of dobutamine in escalating dosages on haemodynamic performance in awake and anaesthetised horses. Methods: Randomised cross-over experimental study. Methods: Six healthy adult horses were enrolled, including both standing and isoflurane-anaesthetised experiments with 1-week washout. Heart rate, mean arterial pressure (MAP), central venous pressure, pulmonary arterial pressure, and...
Obrochta B, Tapio H, Raekallio M, Gracia Calvo LA, Pöyhönen RR, Hagman K, Jantunen N, Karikoski N.Sedation in horses is typically achieved using alpha-2 adrenoceptor agonists, although their use is associated with multiple side effects. A peripheral alpha-2 adrenoceptor antagonist, vatinoxan, can alleviate many of these. Objective: To evaluate the effects of vatinoxan infusion on gastrointestinal motility, sedation, and antinociception in horses sedated with detomidine infusion. Methods: Randomised, blinded cross-over in vivo experiments. Methods: Eight horses were given two 4-h infusions: detomidine (0.01 mg/kg + 0.015 mg/kg/h IV) (DET) and a combination of detomidine and vatinoxa...
Kintz P, Baudry M, Gheddar L.Trazodone, a medicine registered for human, is a serotonin agonist-antagonist. At low dose, the drug is sedative due to its antagonist properties. At high dose, it is an agonist with anxiolytic and antidepressant actions. Trazodone can be administered to the horse to reduce anxiety. However, according to the anti-doping rules for horses, the presence of trazodone in blood or urine is considered as a violation which will produce a suspension of both the athlete and the horse as the drug is listed banned on the International Federation of Horseracing Authorities prohibited substances list. As a ...
Oyaneder L, Lagos N, Dörner C.The present study was conducted to evaluate the safety and the long-lasting anesthetic properties of Neosaxitoxin (NeoSTX) when injected into the intercoccygeal space in standing horses. A group of eighteen (n = 18) healthy client-owned mature crossbreed horses were enrolled in this study. Caudal epidural injection was ascertained by two methods, the "hanging drop" technique and radiographs. Horses were allocated into three groups (n = 6) each group receiving different dosages of NeoSTX. To assess the onset of action and duration of anesthesia, six horses received 20 μg in 2 mL, six 20Â...
Pain management in horses plays a pivotal role in the therapeutic approach to several diseases. Horses have cannabinoid receptors at the level of dorsal root ganglia, blood vessels, and synoviocytes that can be up or down- regulated by inflammatory conditions, justifying the possible efficacy of exogenous cannabinoids (i.e., phytocannabinoids) in managing several painful pathologies in this animal species. However, the current use of supplements containing cannabidiol (CBD) in equines is based on anecdotal evidence, without the support of sufficient pharmacokinetic studies. In humans, the conc...
Yu Y, Wang J, Ruan L, Chen L, Khan MZ, You A, Wang C, Li L, Ren H, Wang T, Liu W.Equid alphaherpesvirus type 8 (EHV-8) is a contagious pathogen that causes reproductive disorders, respiratory diseases, and viral encephalitis in equids, resulting in significant economic losses for the global horse and donkey industries. Currently, there are no approved antiviral drugs or vaccines available for EHV-8 control. In this study, we investigated the antiviral efficacy of celastrol against EHV-8 both in vitro and in vivo. Our results demonstrated that celastrol significantly inhibited EHV-8 infection in Rabbit kidney (RK-13) and equine dermal cells (NBL-6) in a dose-dependent manne...
Kazama T, Hector RC, Hess AM, Rezende ML.To determine the cardiopulmonary effects of oral trazodone before isoflurane anesthesia in systemically healthy horses. Unassigned: 12 horses donated for euthanasia (from August 2022 through June 2023) due to conditions unrelated to the cardiovascular system were included in this prospective, randomized, controlled trial. Horses were assigned to receive oral trazodone (6 mg/kg; n = 7) or corn syrup (n = 5) 1 hour before xylazine (1 mg/kg, IV) sedation, ketamine (2.2 mg/kg, IV) and propofol (0.7 mg/kg, IV) induction, and anesthetic maintenance with inhaled isoflurane (target 1.6% expired) for 7...
Bacon EK, Donnelly CG, Finno CJ, Haase B, Velie BD.Multimodal analgesic administration is a promising strategy for mitigating side effects typically associated with analgesia; nevertheless, variation in analgesic effectiveness still poses a considerable safety concern for both horses and veterinarians. Pharmacogenomic studies have started delving into genetic influences on varying drug effectiveness and related side effects. However, current findings have narrow implications and are limited in their ability to individualize analgesic dosages in horses. Hydromorphone and detomidine were administered to a cohort of 48 horses at standardized time...
Usuga A, Vergara AK, Tobón MC, Vargas S, Rojano B, Restrepo G.Maintaining sperm energy homeostasis in vitro is very important to improve the efficacy of stallion sperm preservation. Equine spermatozoa preferentially utilize oxidative phosphorylation over glycolysis to generate ATP. Metformin and rosiglitazone are antidiabetic compounds that enhances metabolic flexibility and glucose utilization. The aim of this study was to evaluate metformin and rosiglitazone supplementation of the freezing medium on quality and oxidative status of thawed stallion semen. A total of 15 ejaculates from five horses were collected and supplemented before freezing with metfo...
Munsterman AS, Dias Moreira AS, Kottwitz J.To evaluate the effects of detomidine on equine intestinal slow-wave activity and frequency distribution measured by electrointestinography (EIG). Methods: Prospective, experimental study. Methods: University teaching hospital. Methods: A convenience sample of twelve 7- to 21-year-old clinically normal horses. Methods: Horses were randomly assigned to saline control (four horses) or detomidine treatment (eight). After obtaining a 30-min baseline EIG, a saline or detomidine bolus was administered, followed by a constant rate infusion, and another EIG was recorded. Ultrasonographic examinations ...
Chambers A.All anti-doping programmes face financial constraints and monitoring trends in medication use or abuse in a population of racehorses can be difficult and expensive. Obtaining biological samples is the primary method of anti-doping control in individual horses or stables of horses but can be invasive and expensive. Another important practice of anti-doping control has been the confiscation of used and filled syringes by regulators for individual forensic analysis. Pooled samples testing involves the testing of multiple individual samples together as one composite sample. This pooled sample appr...
Hallman IAM, Raekallio MR, Karikoski NP.Vatinoxan is a peripherally acting alpha2-adrenoceptor antagonist used in veterinary medicine to attenuate the side effects of alpha2-adrenoceptor agonists. Vatinoxan also increases insulin response and reduces blood glucose (BG) after intravenous glucose in other species. The aim of this study was to investigate the effects of vatinoxan on BG and insulin concentration in horses after intravenous glucose. The design was an assessor-blind cross-over study. Nine horses were assigned to intravenous vatinoxan (0.2 mg/kg; VAT) or saline (SAL). Horses were administered an intravenous glucose bolus (...
Buzelato Carli I, Fielding L.Many horses receive firocoxib over multiple years, and studies evaluating hematologic and biochemical values in these animals are lacking. Objective: To describe the hematologic and biochemical values of horses receiving long-term firocoxib. Methods: A total of 79 horses receiving long-term firocoxib and 153 horses not receiving long-term firocoxib and not presenting for a specific medical problem. Methods: Retrospective study comparing horses receiving firocoxib (F group) and no firocoxib (NF group). Signalment, hematologic, and biochemical values were compared between the two groups. Simple ...
Cardinaux EM, Oltmanns H, Beineke A, Meißner J, Geburek F.Flexural limb deformities are a widespread condition in foals. Oxytetracycline is a common conservative treatment option with relaxing effects on the muscle-tendon-unit, potentially mediated through a matrix-metalloproteinase (MMP)-inhibitor mechanism. Its high therapeutic dose for this indication, potential negative side effects, and the guidelines for prudent use of antimicrobials make investigating alternatives desirable. In this study, the influence of substances with potentially similar mechanisms of action, however without antimicrobial properties, on viability and proliferation of juven...
El-Ghaly W, El Kamli T, Gongbe AMA, Zaari Lambarki L, El Hamdani M, Lahkak FE, Al Idrissi N, Benmoussa A, Balouch L, Bakkali F, Saffaj T, Jhilal F.The quantification of banned substances in equine antidoping control, especially in racehorse urine, necessitates robust analytical methods with high detection levels due to the extremely low concentrations of the target substances and the significant impact of minor variations on doping test results. Reliable quantification is important for substances near regulatory thresholds, which, if exceeded, are prohibited. This study presents the development and validation of a bioanalytical UHPLC-HRMS method for quantifying doping substances in equine urine, including diazepam and acepromazine with a...
Bianchi D, Santos RRD, Peleja PL, de Sousa ABB, da Silva Evangelista M, de Almeida Júnior JS, Barata LES, Moraes WP, Minervino AHH. (tropical horse tick) is a tick species commonly found parasitizing horses and other equids in the Amazon region, causing economic losses. Currently, tick control is based on chemical acaricides, usually in a power formulation for topical use. However, its indiscriminate use results in the emergence of resistant tick lineages. Several plant compounds have been tested for their acaricide activity. In the Amazon, several plants are used for oil extraction, resulting in the production of solid residue (waste) that may contain chemical molecules with biological activities. Thus, we aimed to test ...
Bardhi A, Barbarossa A, Joubert A, Gehring R, Lambertini C, Romagnoli N.Dried blood spot (DBS) sampling has emerged as a promising microsampling technique in biomedical and clinical research, offering advantages such as reduced invasiveness, minimal blood volume requirements, and enhanced analyte stability. Although well established in human medicine for neonatal screening and diagnostic applications, its potential in veterinary pharmacology remains underexplored. This study investigated the feasibility of using DBS samples to quantify anesthetic agents-ketamine and medetomidine in cats and lidocaine in horses-during routine surgical procedures at a veterinary tea...
Bazzano M, Laus F, Cerquetella M, Spaterna A, Marchegiani A.Phytocannabinoids have the potential to lower intraocular pressure in both normal and glaucomatous eyes and they have been tested in different animal species, but not in the horse. The present paper describes the tonometric curve of healthy adult Italian Saddle horses after oral administration of cannabidiol oil (CBD). Methods: CBD 20% was administered orally (oily solution) at the dose of 1 mg/kg to 8 adult horses and intraocular pressure (IOP) was evaluated by tonometric curve. Data were then compared to those of the same horses obtained the day before (blank) CBD administration. Results: ...
Sobhy A, Nomir AG, Hamed MA, Abumandour MMA, El-Kammar M.The current study was prepared to compare the efficacy of xylazine-lidocaine HCl and detomidine-lidocaine HCl following caudal epidural injection in horses, evaluating sedation, analgesia, physiological parameters, and hemato-biochemical values. This study was applied to six healthy adult horses (300-350 kg, > 4 years of age). The horses were randomly divided into two equal groups. Group 1 (seven horses) received xylazine (0.17 mg/kg bwt) + lidocaine HCl (0.06 mg/kg bwt), while Group 2 received detomidine (0.03 mg/kg bwt) + lidocaine HCl (0.06 mg/kg bwt) via caudal epidural inje...
Tarillion M, Hertzsch R, Richter A.Since 28.01.2022, veterinary medicinal products must be used in accordance with the conditions of authorization (Regulation (EU) 2019/6, Article 106). This entails further restrictions on therapeutic freedom, e. g., with regard to dose deviations. To date, there is no data available in equine medicine on the scope of off-label use as any use deviating from the expert information for antibiotics, on the basis of which the feasibility of implementing the new regulations in Germany can be assessed.To collect data on the off-label use of antibiotics, a Germany-wide anonymous online survey was th...
Bacon EK, Finno CJ, Donnelly CG, Haase B, Knych HK, Velie BD.Clinical assessments of equine sedation typically rely on subjective observations, the accuracy of which is paramount to the safety of equine veterinary procedures. Methods: To assess the degree in which subjective clinical sedative evaluations reflect pharmacokinetic measurements of equine drug metabolism, xylazine hydrochloride, an alpha-2 adrenoreceptor agonist, was administered to 36 horses of varying breed and age at a dosage of 0.5 mg/kg body weight. Subjective clinical parameters were scored at 5-, 15-, 30-, 45- and 60-minutes post xylazine administration and included responsiveness to ...
Mountessou BYG, Mouafon IL, Maharjan R, Tchamgoue J, Tiani GLM, Dibouloul P, Choudhary MI, Kouam SF.Four previously undescribed phenazine-derived pigments (1-4), along with seventeen known compounds, were isolated from a strain cultured on solid rice medium. Structural elucidation of the new compounds was achieved through extensive spectroscopic analysis, while known compounds were identified by comparison with literature data. The antimicrobial and cytotoxic activities of the isolated compounds were assessed. Compounds 2, 5, and 11 exhibited weak antifungal activity against at 200 μM, while compounds 5, 6, 11, 12, 15, and 20 demonstrated moderate antibacterial effects against at the sam...
Jantunen N, Raekallio M, Obrochta B, Tapio H, Gracia Calvo L, Rivera Pöyhönen R, Hagman K, Karikoski N.To assess the effects of a 4 hour detomidine constant rate infusion (CRI) with and without a vatinoxan CRI on energy metabolism and urine composition. Methods: Randomized, blinded, crossover study. Methods: Eight Finnhorses, 587 (550-620) kg [median (range)] and 13 (4-16) years old. Methods: Horses were administered an intravenous (IV) detomidine loading dose (0.01 mg kg) followed by 240 minutes CRI (0.015 mg kg hour) (DET) and the same detomidine protocol combined with an IV vatinoxan loading dose (0.15 mg kg) and CRI (0.05 mg kg hour) (DET+VAT). Blood samples for glucose, insulin, non-esteri...
Bombardi C, Salamanca G, Tagliavia C, Grandis A, Zamith Cunha R, Gramenzi A, De Silva M, Zannoni A, Chiocchetti R.The amygdala is composed of several nuclei, including the lateral nucleus which is the main receiving area for the input from cortical and subcortical brain regions. It mediates fear, anxiety, stress, and pain across species. Evidence suggests that the endocannabinoid system may be a promising target for modulating these processes. Cannabinoid and cannabinoid-related receptors have been identified in the amygdala of rodents, carnivores, and humans, but not in horses. This study aimed to investigate the gene expression of cannabinoid receptors 1 (CB1R) and 2 (CB2R), transient receptor potential...
