HOW TO MANAGE EQUINE ASTHMA
”Equine Asthma”- yep, that's the new name for "heaves," "RAO," "COPD" or whatever else we've called it over the years!
There are two types of this condition, “summer-pasture-associated” and “classic” recurrent airway obstruction (RAO).
Summer-pasture-associated horses tend to be triggered by spring/summer allergens like grasses and trees, and “classic” horses tend to be triggered by barn dust and mold spores. Most horses in our area of North Carolina are "Summer-Pasture-Associated" asthma patients, so we recommend starting yearly treatment or management in March or April. It’s important to know, however, that some horses can have BOTH types, and will need to managed year-round!
What are your treatment and management options? Read on below!
There are three main medication protocols for horses with Equine Asthma.
1: Systemic treatment with steroids. This usually involves treatment with dexamethasone or prednisolone (we prefer dexamethasone). This is the easiest and least expensive treatment option, but comes with risks. There's a small risk that the horse could develop laminitis, and the steroids can suppress their immune system. Due to the risk of laminitis, this option isn't usually a good choice for horses with metabolic diseases like PPID/Cushing's or Equine Metabolic Syndrome. Systemic steroids are also a problem if you show in any recognized events or disciplines with drug and medication rules.
2: Inhaler therapy. This has long been thought of as the "best" option for horses with Equine Asthma. This involves the use of a special mask to deliver human inhaler medications to the horse. There's very little risk to this treatment, it's typically very effective, and shouldn't be problematic for those that show. The biggest issue is in obtaining the actual inhalers (some have been discontinued) and the skyrocketing costs of the inhalers.
3: Nebulizer therapy. This is becoming a more common option for the treatment of Equine Asthma, since inhalers have become so expensive. An equine specific nebulizer (Flexineb), can be used to deliver inhaled medications to the lungs. There haven't been many studies on this therapy yet, but it's becoming pretty common and seems to be very efffective. While the nebulizer itself is expensive, the ongoing monthly treatment costs are comparable to the cost of systemic steroids (very inexpensive).
DIET AND MANAGEMENT:
1. The Feed: One of the most common recommendations for managing Equine Asthma has always been to stop feeding hay. While this is a very important strategy for some types of Equine Asthma ("classic" RAO), it may not be as important when managing those with Summer-Pasture-Associated disease. I often recommend switching your Asthma horse off of regular hay and trying a period of hay-replacement to see if it helps. Hay replacement consists of any of the following: a complete pelleted diet, soaked alfalfa cubes, hay pellets, or possibly a bagged forage product like Chaffhaye. Once you have the horse's symptoms under control, you can try re-introducing hay. If your horse worsens when hay is re-introduced, you'll need to consider a permanent change to one of the other options!
2: The Barn and Pasture: Horses with Summer-Pasture-Associated disease usually have less symptoms when kept in the barn during the warmer months. Since some horses have both "types" of asthma, you may need to try a stall without bedding, or experiment with different types of bedding. If your horse has "classic" RAO, he may have more difficulty in the barn, and need to be kept outside 24/7.
3: The Supplements: Studies have shown that horses with Asthma benefit from supplements with Omega 3 fatty acids. Look for a supplement with at least 1,500mg of DHA per serving. We recommend Platinum Skin and Allergy or Aleira.
So what else can we do for our Equine Asthma patients?
Acupuncture: It appears that some horses with Equine Asthma can benefit from acupuncture to help with breathing function. Typically, a few sessions are required.
Apoquel: This medication (tablets) is approved to control allergic itching in dogs. Some veterinarians have used the medication for Equine Asthma, and have had variable results. The medication is expensive, but could be worth a try in some horses.
Zyrtec: The human antihistamine may be beneficial in a small proportion of horses with Equine Asthma. Since the vast majority of Equine Asthma patients do not have a histamine-associated problem, this isn't likely to work for most. If your horse's test results (from a BAL or tracheal wash) show a certain cell type in the lungs, we may recommend trying Zyrtec!
Clenbuterol: This is a bronchodilator that may be beneficial in treating some horses with Equine Asthma. Clenbuterol dilates the airways, and may improve air flow, but it doesn't treat the inflammation associated with the disease. Clenbuterol should only be used short-term, since it will stop working with long-term administration.