Blog

What are Horse Hives, and How Can I Prevent Them?

Sort Posts

It always happens the same way. You go out to visit your beloved equine companion to give him his evening meal, and when he comes into eyesight, you have to pick your jaw up off the floor. Your horse appears to have more bumps and lumps on his body than hair on his head! 

You immediately assume that he is dying (we always jump to the worst conclusion, especially with our horses)! Upon further inspection, you note that he isn’t in any pain, just maybe a bit itchy and seems to only be impatiently putting up with this impromptu exam so he can get his feed. 

Putting in a call to the vet immediately comes to your mind and after you get them on the way you begin to try and piece together the puzzle.  Did he get into something he shouldn’t have? Is he allergic to bugs? Hives aren’t always the easiest to figure out. So, hopefully this blog post will help you eliminate some possible causes of your horse’s hives.

What Are Hives

Hives (urticaria) is an outbreak of swollen, red bumps on the skin that come up suddenly. On a furry horse, it may look like the horse’s fur is covering bubble wrap. These bumps are usually a result of the body’s reaction to certain allergies. Allergic reactions are the most common cause of hives. During the summer months, hives often show up as a response to insect bites. This can be from horseflies, gnats, etc. 

With all of the things horses come into contact with, it is usually difficult to pinpoint what exactly is causing the reaction. Hives can appear anywhere on the body. Substances that can cause a horse to break out in hives may be ingested (feed, supplements, any oral medication, etc.), maybe medications given by injection (such as vaccines, phenylbutazone, or penicillin), or maybe due to contact with the skin (bedding, tack or blankets, or topically applied substances such as fly sprays or certain shampoos). Contaminants in hay or feed such as mold or other allergens that are inhaled may also cause a horse to get hives.

How to Treat Horse Hives

Many cases of hives resolve themselves in 24-72 hours. Other cases may resolve only to come back days later, while persistent cases may not go away at all. When your veterinarian comes to check out the situation he/she will usually give a single dose of a short-acting corticosteroid that will usually help the hives go away.

The ideal therapy for preventing hives from plaguing your horse is to avoid or eliminate the triggering factors. Simple steps you can take include changing paddocks and bedding, eliminating supplements (at least for a trial period to see if this is what is causing the reaction), and going over any recently added medications with your veterinarian. Recurrent or persistent hives may be treated with a more routine administration of low doses of steroids which can be kept at the barn (in your equine first aid kit). However, if the horse is prone to laminitis this may not be advisable.

Skin testing may also help the horse with recurring hives because it is the most effective way to determine your horse’s level of allergic response. A small amount of serum containing different allergens is injected into your horse’s skin, and the size of the bump it creates correlates to the degree of your horse’s allergic response. This is done very similarly to when people get allergy tested.

Carolina Equine Hospital

Did your horse show up to the barn looking like he has been eaten alive by mosquitoes? Give us a call at 336-349-4080 to schedule an appointment to get him checked out! While some hives occur conveniently during work hours, some wait to pop up after hours. Luckily, we have an emergency vet on call 24/7. So, we are always able to help!