Category Archives: Horses

Use of Aerosolized Bronchodilators and Corticosteroids

In recent years, aerosolized drug therapy in the horse has transitioned from a curiosity to a well established treatment modality. Practitioners and owners alike have recognized the benefit of topical application of bronchodilator and glucocorticoid drugs, thus avoiding the side effects and even toxicities associated with the systemic delivery of these drugs. Although several publications… Read More »

Treatment Modalities

Aerosolized drugs can be used to provide both quick relief of respiratory difficulty and long-term treatment (Table Recommended Dosages for Aerosolized Medications in Horses). Quick relief can be provided by short-acting β2-adrenergic agonists or anticholinergic drugs. Long-term therapy is provided by use of antiinflammatory drugs and perhaps long-acting β2-adrenoceptor agonists. Table Recommended Dosages for Aerosolized… Read More »

Sample Treatment Regimens

Case 1 The typical horse with moderate recurrent airway obstruction may have 30% to 70% neutrophils in the bronchoalveolar lavage fluid, resting airway resistance that is elevated twice to three times normal, and visible signs of increased breathing effort. This horse would show a 30% to 50% reduction in airway resistance after receiving 450 meg… Read More »

Aerosolized Drug Delivery Devices

Aerosolized drug therapy has been the standard treatment approach in human medicine for patients with noninfectious respiratory disease for 20 years. Administration via inhalation improves drug safety and efficacy by reducing the total therapeutic dose, minimizing drug exposure to other body systems, and allowing direct delivery of the drug to the lower respiratory tract. In… Read More »

Metered-Dose Inhalant Systems

Several devices have been designed for convenient administration of aerosolized drugs formulated in a metered-dose inhaler () cannister to horses with recurrent airway obstruction (). The advantages of an metered-dose inhaler system include rapid administration, consistent ex-valve dose delivery, minimal risk of pulmonary contamination with environmental microorganisms, ease of cleaning/maintaining equipment, wide availability, and no… Read More »

Dry Powder Inhalant (DPI) Devices

Dry powder inhalant devices offer several advantages over nebulization systems, including rapid drug administration, minimal risk of environmental contamination with drug, and no requirement for electricity. The dry powder inhalants comprise numerous capsules containing a single dose of drug and a rotor. The rotor of the dry powder inhalant device is breath-actuated, and the device… Read More »


Diagnosis of Pneumothorax Pneumothorax occurs whenever air enters the pleural cavity and compromises the negative pressure that keeps the lungs expanded and allows the horse to breathe. Pneumothorax can be secondary to blunt trauma, penetrating wounds to the thorax from sharp objects, gunshot entry tracts, or barotrauma, or it may arise spontaneously. Open pneumothorax is… Read More »

Diaphragmatic Hernia

Diaphragmatic hernia in horses is uncommon but not rare. Most referral practices are presented with one or more cases annually. The causes are associated principally with trauma to either the thorax or abdomen, but the injury also can occur after exertion such as that experienced by stallions during breeding. Congenital diaphragmatic hernia can occur in… Read More »

Fractured Ribs

Fractured ribs most commonly are observed in neonates in conjunction with birth trauma. Rib fractures in older individuals most often result from collisions or kicks or falls. Birth trauma is the most common cause of rib fracture, and most neonates with fractures do not require medical or surgical intervention. However, rib fracture can cause life-threatening… Read More »

Exercise-Induced Pulmonary Hemorrhage

In exercise-induced pulmonary hemorrhage (EIPH) blood is present in the airways after exercise. The most frequent classification of horses as exercise-induced pulmonary hemorrhage positive or negative is currently based on postexercise endoscopy. Until the introduction of endoscopy and surveys of horses after racing, it generally was considered that only few horses experienced exercise-induced pulmonary hemorrhage,… Read More »