Environmental modification is the cornerstone of equine asthma management and must accompany all pharmacologic therapy — corticosteroids and bronchodilators alone are insufficient without reduction or elimination of triggering airborne antigens. Veterinary Clin…+2 Clinical signs resolve within 3–4 weeks of appropriate environmental changes alone. Macedonian Vete…

For acute exacerbation with labored breathing at rest, rescue bronchodilation is the immediate first priority. Inhaled albuterol (salbutamol) produces a 61.1% decrease in transpulmonary pressure and has a duration of action of 60 minutes. Journal of Vete… Inhaled levalbuterol achieves an equivalent magnitude of bronchodilation (59.9% decrease in transpulmonary pressure) with a duration of action of 120 minutes, but this remains too short for use as a maintenance bronchodilator; both agents are therefore limited to rescue or diagnostic use. Journal of Vete…

Corticosteroids are the most effective anti-inflammatory drugs for severe equine asthma. Among systemic agents, dexamethasone is the most potent in comparative studies; triamcinolone, isoflupredone, and prednisolone are also efficacious. Equine Veterina… Systemic corticosteroids are associated with adrenal suppression, decreased immune function, and possible laminitis with prolonged use, and clinical signs relapse soon after cessation in the absence of environmental intervention. Equine Veterina… For this reason, systemic corticosteroids are typically administered for days to weeks only. Equine Veterina…

Inhaled corticosteroids are the preferred long-term anti-inflammatory strategy, providing equivalent efficacy to systemic dexamethasone at appropriate doses with a more favorable safety profile. Inhaled fluticasone and beclomethasone at appropriate doses produce equivalent effects on severe equine asthma as intravenous dexamethasone, though inhaled corticosteroids take longer to achieve the desired effect. Veterinary Evid… Inhaled budesonide, delivered via a Respimat-based equine device, improves lung function to a similar magnitude as systemic dexamethasone at higher dosages; both effectiveness and cortisol suppression are dose-dependent. Equine Veterina… Inhaled ciclesonide (Aservo Equihaler) effectively ameliorates clinical signs of severe equine asthma and is well tolerated in field conditions. Equine Veterina… A clinical score of ≥11 on the adapted Tesarowski scoring system, combined with labored breathing at rest, is used to confirm exacerbation severity and enroll horses for corticosteroid treatment trials. Equine Veterina…

Tamoxifen represents an adjunct therapy targeting airway neutrophilia, a component that corticosteroids and bronchodilators consistently fail to normalize. Journal of Vete… Tamoxifen increases apoptosis of peripheral and pulmonary neutrophils and improved clinical condition, airway neutrophilia, and mucus accumulation in horses with experimentally induced asthma-like inflammation. Journal of Vete… Standard corticosteroid monotherapy consistently fails to improve airway cytology despite reversing airway obstruction. Equine Veterina…

Nanoparticulate CpG-oligodeoxynucleotide (CpG-ODN) immunotherapy delivered via gelatin nanoparticle inhalation is an emerging adjunct that redirects the immune response from a pro-allergic Th2 toward a Th1 pathway. Journal of Vete… A regimen of one inhalation every 2 days for 5 consecutive administrations produced significant decreases in respiratory effort, nasal discharge, tracheal secretion viscosity, and airway neutrophil percentage, with increased arterial oxygen pressure; effects persisted at 4 weeks post-treatment. Journal of Vete…

Would you like to go deeper on the comparative dosing and safety profiles of the available inhaled corticosteroids — budesonide, ciclesonide, fluticasone, and beclomethasone — for long-term maintenance?