Faculty members of Equine Internal Medicine at Kansas State University have been intently focused on reactive airway disease, also known as heaves, and the effects of aerosolized treatments in horses. Associate Professor Dr. Bonnie Rush and her colleagues have been concentrating on developing systems that will effectively and efficiently deliver aerosolized drugs to the lower airway. A horse with heaves is similar to a human with asthma. Horses tend to be most susceptible or reactive to molds, organic dust, straw, and, occasionally, pollen in the spring and late summer. Another similarity to human asthma is that there is a broad spectrum of symptom severity.
Some horses intermittently have trouble breathing during exercise.
In severe cases, horses may have difficulty breathing at rest. The typical age of onset of heaves is about eight years. While aerosolized drugs have been the mainstay of treatment for human asthma for at least fifteen years, the concept is still being developed in equine medicine. Systemically administered drugs have been most commonly used due to the difficulty of administering aerosolized drugs. The main advantage of aerosolized drugs is that a smaller dosage can be delivered directly to the airways, which reduces the risk of adverse effects and improves the efficiency.