Aches, pains and fevers are often a part of life. They are for people and they are for horses as well. Just as we have medication in our medicine cabinet for our relief for these discomforts relief for horses often comes in the form of bute. Phenylbutazone, more commonly known as bute, is an anti-inflammatory and analgesic, or pain relieving drug for horses. It is sometimes called NSAID which stands for non steroidal anti inflammatory drug.
Aspirin and ibuprofen are also NSAIDs. Bute is often a favorite choice because it is less expensive than other anti inflammatory drugs. It is convenient to give to horses because it is only given once or twice a day. Bute is available as one gram tablets that must be ground and made into a powder to administer orally, in a tube (like a dewormer) ready to give orally. Both are ways an individual may give the horse themselves. Bute is also available as a drug your veterinarian can inject.
Bute can have side effects. One common side effect that can appear in just a few days after giving a horse bute is ulcers. Ulcers can occur in the stomach of the horse or other places in the digestive tract. They can form anywhere from the horses mouth all the way through the colon. If a horse loses his appetite while bute is being administered for a while that can be a sign of an ulcer. Other signs the horse might have an ulcer could be eating less, especially grain, or taking longer than normal to finish his food. Another side effect of bute is kidney damage. Long term use of phenylbutazone can damage a horse’s kidneys.
Local irritations like mouth sores can be caused by using injected bute. It can also impede the intestine of the horse inhibiting its natural ability of secreting a layer of protective mucus that normally guards against acids and other irritants. Giving bute in this form can be inconvenient also as it is usually given by a veterinarian. Bute can act like a blood thinner. It can affect the ability of the blood to clot. This can be particularly dangerous to horses that are “bleeders”. Bute may cause some lowering of blood counts. It is rare but it can affect the bone marrow and also cause bleeding from the intestinal tract.
There are ways to minimize side effects when administering bute. If you choose to crush the tablets and give as a powder it may be mixed with a milk of magnesia mixture. This mixture must be placed into a clean syringe and is to be squirted into the horse’s mouth, like a paste dewormer. This can be messy. If the horse spits it out you have to begin again. You must push the syringe as far back into the horse’s mouth as you can before squirting. You must also keep the horse’s head up so he will swallow and not spit the mixture out.
Powdered bute may also be given mixed into the horse’s grain. Bute is very bitter and he probably will choose not to eat it. A horse can pick through the grain and leave the bute at the bottom of the bucket. Adding a flavored milk of magnesia can help to protect the horse’s stomach. It may also help disguise some of the bitter taste of bute providing your horse likes the flavor you choose. You may also need to try adding grape juice, apple sauce, molasses, or even some cooking oil to try and cover the bitter taste to make it more palatable for the horse.
If bute is given with food it can present a problem with absorption of the drug. It can even lead to an accidental overdose. If given within a couple of hours of feeding hay bute can bind to the hay in the intestinal tract. It can stay there for days instead of being immediately absorbed. This will delay the immediate benefit of the bute. If bute is given for more than one day the previous day’s dose can combine with the first day’s dose that can still be in the horse’s digestive tract. It can bind to the hay causing a buildup.
This can lead to an overdose over the period of a few days. There are times your horse needs medication. The side effects caused by bute do not mean you should refuse to give it to your horse. Short term use of bute will have the lowest incidence of side effects. Bute should not be used casually. It is a prescription drug. Use bute intelligently and in doses for the purposes it has been prescribed by your veterinarian.