All in all, vaccine reactions are very rare, and the process of vaccination against a disease process is one of the best ways you can safeguard your horse’s health. Vaccination is one of the most impressive discoveries of modern medicine; the ability to protect a horse against the ill effects of several severe and often fatal diseases is a huge benefit. However, you should understand the risks, and discuss potential reactions beforehand with your veterinarian, in case your horse is one of the few who suffer from a reaction.

Local Vaccine Reactions

Vaccines can sometimes cause local reactions and even some systemic effects. The most common reaction (RXN is the medical abbreviation) to a vaccination is most likely to be a simple stiff neck. Generally, the neck soreness does not cause a problem and will resolve on its own in a few days. Where it does cause a problem is if you are unaware that it can happen and vaccinate on Wednesday or Thursday and think you are going to a show on Saturday, only to find out that the horse won’t bend or move his neck very well. If a lump forms or the muscle around the injection site becomes very hard, you can use a cold pack and administer oral phenylbutazone (Bute). If the swelling does not subside after a few days, the area can be hot-packed with a hot towel (placing a hot bran mash inside a Ziploc bag works very well for hot-packing) four to six times per day for 10-15 minutes each time.

As many of you might have experienced with the human flu vaccine, it is not uncommon to spend a day or two of “not feeling quite right” after receiving a vaccination. Horses are no different and can become slightly depressed or develop a poor appetite for 24-48 hours after vaccination. The important thing is that they should not develop a significantly abnormal temperature (up to 101.5°F can be caused by vaccine stimulus, but a higher fever should be evaluated further), or abnormal heart or respiratory rate. If the vital signs are abnormal or the mild depression/inappetence continues for more than 48 hours, the horse should be examined by a veterinarian

Create a free account with TheHorse.com to view this content.

TheHorse.com is home to thousands of free articles about horse health care. In order to access some of our exclusive free content, you must be signed into TheHorse.com.

Start your free account today!

Already have an account?
and continue reading.