What you see. The starting point for addressing any equine health related issue is your observation.


Bute, Banamine®, NSAID Overdose, Excessive Amount Given


NSAIDS for horses are prescription drugs and should only be used under your vet's supervision. NSAIDS have a narrow safety margin in horses, and it is fairly easy to overdose them.

Overdoses of NSAIDs can cause life-threatening damage to the equine intestine and kidneys. These drugs are intended to be used once or twice daily, no more, and at a dose prescribed by your vet.

Occasionally, a person will accidentally give too much phenylbutazone or other NSAID to a horse. This most commonly happens in ponies and younger horses, who are more susceptible to the effects of NSAIDs and are more easily overdosed using small amounts of these drugs. Rarely, a whole tube of phenylbutazone is accidentally given to a horse.

More commonly, toxicity is caused by large doses repeatedly given over time.

  • Code Red

    Call Your Vet Immediately, Even Outside Business Hours

your role


What To Do

Talk to your vet immediately about your concern, noting the amount(s) given and when. Assess your horse's general health using the Whole Horse Exam (WHE), paying particular attention to attitude and appetite, heart rate, rectal temperature and appearance of urine and manure.

What Not To Do

Do not take a "wait and see" approach. Once the damage is done, it is much harder to treat the horse successfully.

your vet's role

Your vet will help you determine whether they need to examine and treat your horse. Early and aggressive prophylactic nursing care (especially IV fluids and certain protective medications) may reduce the harmful effects of a NSAID overdose.
Questions Your Vet Might Ask:
  • What drug and dose was given, and when?
  • How many doses of medication have been given to your horse, and over what period of time?
  • How is your horse's attitude and appetite?
  • How large is your horse?
  • What is the horse's age, sex, breed and history?
  • Why did you first give the NSAID to the horse?
  • What are the results of the Whole Horse Exam (WHE)?

further reading & resources

Author: Doug Thal DVM Dipl. ABVP