You probably won't be in the horse world too long before you hear about the drug Butazone, Pheynl-butazone, PBZ or 'bute' as it's often called (there are also trade names). It's use is very common in equine veterinary practice. Butazone is a non-steroidal anti-inflammatory drug. It is somewhat like ASA commonly taken by people for aches, pains and headaches. That means that bute is a drug that will help relieve inflammation and pain, but is non-steroidal. Very basically, steroids reduce inflammation and pain, but also increase cell growth that promotes healing. In the case of an injury this may be beneficial. But if there is an ongoing problem like arthritis or laminitis, a NSAID like Butazone might be more appropriate.
Bute is recommended for short term use. But many of us have senior horses that have issues like ring bone, side bones, arthritic pain or ongoing laminitis issues that are on bute for a much longer time. Sometimes Bute is used until a better medication is found and sometimes the horse's quality of life has to balanced against possible side effects.
There are some risks to using bute, especially long term. Butazone can cause ulcers and other gastrointestinal problems, blood disorders, kidney damage and can cause serious side effects when combined with other drugs. And although bute was once administered to humans for various health issues, it is no longer and it's recommended that you be very careful not to accidentally inhale or eat it.
Bute can be administered as a paste that can be put directly in the back of the horse's mouth similar to paste wormer, powder that can be sprinkled on feed, pills or it can be injected into a vein. The most common way horses are given bute is powder or crushed pills that can be hidden in food, and perhaps mixed with applesauce or molasses to hide the bitter after-taste. Horses can get suspicious of foods that have medications mixed in, so sometimes we have to be creative to get the medication into them.
Another problem with using bute for horses that ridden and driven is because of the drug's pain killing effects. A horse may injure itself or may further irritate conditions without knowing it. Because the horse can't feel the pain, it can't react to it-and the rider or driver may not notice there's a problem until much later when more damage has been done. The use of bute in performance horses must be used with caution. Many sports such as distance riding will not allow a horse to compete if bute has been administered. Rules vary, so it's important to check, and be aware if your horse may be subject to drug testing.
Bute has been an issue in the debate about horse slaughter. Many people who are against horse slaughter argue that Butazone remains in the meat and can pose a risk to humans who eat the meat. Withdrawl times have been debated and regulations have been attempted to keep horses that have been treated with Butazone out of the food chain. But because bute is so commonly used and horses are not raised as meat animals, keeping horses that have been treated with bute out of the food chain means very few horses would be left to enter it. Bute is on the list of drugs not permitted in food animals for export to the European Union and horses destined for slaughter within Canada. The difficulty is determining which horses have and have not received bute, as there has been no reporting process.