Aerosolized albuterol sulfate used as a bronchodilator in horses with recurrent airway obstruction
Derksen, F.J.; Olszewski, M.A.; Robinson, N.E.; Berney, C.; Hakala, J.E.; Matson, C.J.; Ruth, D.T.
American Journal of Veterinary Research 60(6): 689-693
1999
ISSN/ISBN: 0002-9645 PMID: 10376893 Document Number: 503664
19 horses with recurrent airway obstruction (RAO) (10 in experiment 1; 9 in experiment 2) were used to determine the dose of aerosolized albuterol sulfate required to cause bronchodilation and duration of this effect. Horses were moved from pasture to stables, and airway obstruction was induced. Pulmonary function was measured in 10 horses before and 5, 10, and 30 minutes after administration of vehicle or 120, 240, 360, or 720 micro g of the drug. Nine horses received vehicle or 360 or 720 micro g of albuterol, and pulmonary function was measured at baseline and 5 minutes and 1, 2, 3, 4, 5, 6, and 7 hours later. 360 micro g of albuterol was required to cause significant bronchodilatation; 720 micro g did not enhance bronchodilatation or increase duration of action. Depending on which pulmonary function parameter was evaluated, bronchodilatation achieved by use of albuterol lasted between 30 minutes and 1 hour. Because there was a significant vehicle effect, the combined effect of vehicle and drug lasted up to 3 hours. Adverse effects were not observed. It is concluded that aerosolized albuterol, 360 or 720 micro g, is a safe and effective bronchodilator in horses with RAO. Onset of action is rapid (5 minutes), and effects last from 30 minutes to 3 hours. Aerosolized albuterol is useful for treatment of bronchospasm in horses with RAO.