Dexamethasone is a synthetic glucocorticoid commonly used in equine medicine for its anti-inflammatory and immunosuppressive properties. It is employed in the management of various inflammatory and allergic conditions in horses, such as arthritis, respiratory diseases, and skin disorders. Dexamethasone works by inhibiting the release of inflammatory mediators and suppressing immune responses. Its administration can be through oral, intravenous, or intramuscular routes, depending on the specific clinical situation. This page compiles peer-reviewed research studies and scholarly articles that investigate the pharmacokinetics, therapeutic applications, and potential side effects of dexamethasone in equine health.
Swerczek TW.Four experiments were performed to elucidate the pathogenesis of toxicoinfectious botulism in horses and foals. Groups of horses and foals were inoculated with one of the following: (1) crude toxin of Clostridium botulinum, type B, given IV, (2) C botulinum spores, given IM, (3) C botulinum spores, given IM, in necrotic lesions, and (4) C botulinum spores, given orally with and without dexamethasone. Toxin of C botulinum in minute amounts is toxic to horses. Clostridium botulinum spores produced toxicosis only when necrotic lesions were present. When C botulinum spores were given orally, they ...
Jeffcott LB, Rossdale PD.The efficacy and safety of oxytocin, dexamethasone and prostaglandin, used alone or in combination as inducing agents, are discussed. It is contended that insufficient evidence exists to support the routine application of any of these methods in practice. Oxytocin has been the most widely used and it is claimed by some to be free from side effects. However, the synthetic prostaglandin analogue, fluprostenol, seems to pose the least risk to the foetus and dexamethasone appears to be either ineffective, or too dangerous to use at all. The main indications for induced foaling are managerial conve...
Kono Y, Hirasawa K, Fukunaga Y, Taniguchi T.Horses which had passed a few months to a few years asymptomatically after the last recurrence of equine infectious anemia (EIA) showed a typical febrile response after treatment with the immunosuppressive agent, dexamethasone (DM) or cyclophosphamide (CY). In horses showing a febrile response, EIA virus which had not been neutralized by neutralizing antibody previously produced was propagated. In DM-treated horses it disappeared from the blood soon after pyretolysis and antibody against the virus was produced promptly. In contrast, detectable viremia persisted in CY-treated horses for 10 to 8...
Alm CC, Sullivan JJ, First NL.Dexamethasone (100 mg/day) injected from Days 318 to 324 of pregnancy induced parturition. Progesterone (500 mg/day) administered daily from Day 318 of pregnancy also shortened gestation while oestrogen (50 mg/day) administered on the same schedule as progesterone had no such effect. Dexamethasone treatment superimposed on the oestrogen or progesterone treatments shortened gestation. Prostaglandin F2alpha alone did not induce parturition, unlike PGF2alpha with dexamethasone, or PGF2alpha given to ovariectomized mares.
Chen JW, Uboh CE, Soma LR, You Y, Jiang Z, Li X, Guan F, Liu Y.Animal sport such as horseracing is tainted with drug abuse as are human sports. Treatment of racehorses on race day with therapeutic medications in most cases is banned, and thus, it is essential to monitor the illicit use of drugs in the racing horse to maintain integrity of racing, ensure fair competition and protect the health, safety and welfare of the horse, jockeys and drivers. In the event of a dispute over the identity of the sample donor, if the regulator can provide evidence that the DNA genotype profile of the post-race sample matched that of the alleged donor, then the potential d...
Milam SB, Mackay RJ, Skelley LA.Secretion of tumor necrosis factor (TNF) by equine mammary exudate macrophages (MEM phi) exposed to bacterial lipopolysaccharide (LPS) was dose-dependent and was maximal (216.5 +/- 51.9 U/ml) at 100 micrograms LPS/ml, the highest concentration tested. All concentrations of dexamethasone tested (10(-8) to 10(-4) M) significantly (P less than or equal to 0.05) inhibited TNF production by MEM phi when the agent was added 1 hour before LPS. Pretreatment with pentoxifylline at concentrations greater than 3 micrograms/ml also significantly (P less than or equal to 0.05) reduced secretion of TNF by M...
Guelfi JF, Kraouchi DE.Chemotaxis and superoxide anion production of neutrophils in healthy horses were investigated before and 8 h after, a single injection of dexamethasone at a dose of 0.045 mg/kg. Chemotaxis was studied by the technique of migration under agarose and superoxyde production was measured by ferricytochrome c reduction. Superoxide anion production was not changed, but the chemotactic index, with zymosan activated horse serum, was increased. The FMLP chemoattractant effect, at 10(-4) M, was slightly enhanced.
Zetterström S, Groover E, Lascola K, Cole R, Velloso A, Boone L.A five-year-old Thoroughbred mare was evaluated because of chronic, malodorous, unilateral nasal discharge, and suspected maxillary cheek tooth root abscess. Skull radiographs revealed bilateral sinusitis suspected secondary to tooth root abscessation of 109 and 210. Following oral extraction of 109, bilateral conchofrontal sinus trephination and lavage; fever, tachycardia, and cervical stiffness developed. A lumbosacral cerebrospinal fluid tap was performed, and a presumptive diagnosis of bacterial meningitis was made. Targeted therapy consisted of antibiotic treatment with penicillin, enrofl...
Authie EC, Garcia P, Popot MA, Toutain PL, Doucet M.Equine antidoping rules were established to prevent a horse's performance being altered after the administration of prohibited substances, including approved drugs used for legitimate treatment. Veterinarians have to advise owners or trainers on appropriate withholding times to guarantee that their horses may safely compete after drug administration. In order to propose tailored withdrawal times, several horse organisations released detection time (DT) values, for the main veterinary drugs used in horses. One of the possible limits to the information provided by published DTs in horses is the ...
Turn JT, Mayer J, Nagata K, Banovic F, Meichner K, Hurley DJ, Koslowski E, Gogal RM.Apitherapy is a form of alternative medicine that utilizes products from the western honeybee (Apis mellifera), including honey, propolis, and honeybee venom, to improve the health status of human patients by altering host immunity. An added benefit of these products is that they are nutraceuticals and relatively inexpensive to aquire. Currently, little is known about the use of honeybee products in veterinary species, as well as their impact on host immunity. In the present in vitro study, honey, propolis, and honeybee venom were co-cultured with enriched canine, equine, and chicken periphera...
Heidari N, Faragher RGA, Pattison G, Dudhia J, Smith RKW.Tendinopathy is a common age-related disease which causes significant morbidity for both human athletes and performance horses. In the latter, the superficial digital flexor tendon is an excellent model for human tendinopathies because it is a functional homologue of the human Achilles tendon and a primary site of injuries with strong similarities to the human disease. Corticosteroids have been previously used clinically to treat tendinopathic inflammation, but they upregulate the p53-p21 axis with concomitant reductions in cell proliferation and collagen synthesis in human tenocytes. This phe...
Palmer AT, Watts MR, Timko KJ, Pinnell EF, Keefer KA, Gorman O, Hostnik LD, Burns TA.Corticosteroids are used routinely in horses and induce insulin dysregulation (ID). Nutrition is important for ID management and includes low nonstructural carbohydrate (NSC) diets and, often, high-protein ration balancers (RB). Insulin and incretin secretion increase after high-protein meals; corticosteroids may influence these effects. Objective: A high-protein mixed meal will induce hyperinsulinemia and increased concentrations of glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1 (GLP-1) in horses with ID; dexamethasone (DEX) will amplify this effect. Methods: F...
Roccaro M, Rinnovati R, Stucchi L, La Rocca F, Cascio G, Peli A.Doping in racehorses is a threat to horse welfare and the integrity of the sport. Despite its relevance, the literature on the prevalence of anti-doping violations worldwide is limited. Objective: To analyse anti-doping violations in racehorses in Italy. Methods: Retrospective observational study. Methods: Data on horse races, anti-doping testing, and confirmed violations between 2014 and 2022 were collected and analysed. Positivity rates, most common drug classes and parent drugs, and differences between trotting and galloping horses were investigated. Results: During the considered 9-year ti...
Osorio-Cardona JJ, Usuga-Moreno VM, Martínez-Aranzales JR.The dexamethasone suppression test (DST) has been used in humans for the diagnosis of psychiatric problems such as depression, anxiety and Cushing's syndrome, and in horses for the ante mortem diagnosis of dysfunction of the intermediate part of the pituitary. Objective: This study aimed to examine the functionality of the hypothalamic-pituitary-adrenal axis through the DST and the cortisol index (CI), to evaluate the rhythmicity of the circadian cycle of cortisol in healthy horses with crib-biting or windsucking. Methods: A total of 20 Colombian Creole horses of both sexes, under similar mana...
Hendrikx AL, Vendrig JC, Gehring R, van den Boom R, van Alphen J, Vernooij JCM, Teske E, Roelfsema E.To determine the effect of repeated IV administration of dexamethasone (0.06 mg/kg, q 24 h, twice) on WBC parameters in healthy adult horses. Unassigned: This prospective, longitudinal study was conducted from October 7 through November 5, 2024. Five warmblood mares received an IV dexamethasone sodium phosphate injection (DMI) at 0 and 24 hours and an IV injection with 0.9% sodium chloride solution at 48 and 72 hours. Blood samples were collected at 0, 6, 12, 24, 30, 36, 48, 72, 96, and 168 hours, and WBC parameters were evaluated using linear mixed-effects models. Unassigned: Leukocyte count,...
Tyson KN, Couetil LL, Ivester KM, Murray L, Mukhopadhyay A, Marmolejo JF, Jannasch A.Nebulization of injectable dexamethasone sodium phosphate (DSP; 0.01 mg/kg) to horses with severe equine asthma (SEA) was previously found to be ineffective. Horses with SEA have marked bronchoconstriction that decreases peripheral lung deposition of nebulized drugs. Administration of a bronchodilator immediately before nebulizing dexamethasone may improve efficacy. Objective: Evaluate the therapeutic effects and optimal dose of nebulized DSP after nebulized albuterol in horses with SEA. Methods: Seven horses with SEA from a research herd. Methods: In this masked randomized crossover trial, h...
Bertin FR, van Eps AW, de Tonnerre DJ, Kulp JC, Stefanovski D.Dexamethasone is used to experimentally induce insulin resistance; however, its impact on insulin secretion is unclear. This study aimed to assess the responses to oral carbohydrate challenges in dexamethasone-treated horses. Unassigned: 8 healthy Standardbreds received 0.08 mg/kg of dexamethasone IM every 48 hours for 14 days in June 2022 (winter in the Southern hemisphere). Oral glucose tests (OGT) were conducted before treatment (day 1) and on days 8 and 15. Glucose, insulin, triglycerides, total and active glucagon-like peptide-1 (tGLP-1 and aGLP-1) and glucose-dependent insulinotropic pol...
Olakojo TA, Akinniyi OO, Dansu EO, Adeoye AO, Adah O, Nwufoh OC, Adeoye BO, Oridupa OA, Saba AB.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...
