Butatron is a non-steroidal anti-inflammatory drug. Its main ingredient is phenylbutazone (PBZ), the most commonly used non-steroidal anti-inflammatory drug (NSAID) in equine practice. In dogs and horses, the drug is used for the relief of inflammatory conditions associated with a musculoskeletal system. It has anti-inflammatory, antipyretic, and analgesic activities. Butatron has been used in ankylosing spondylitis, rheumatoid arthritis, reactive arthritis and acute attacks of osteoarthritis of the hips and knees not responsive to other treatments.

Phenylbutazone is banned for use in any animal intended for human consumption because it causes serious and lethal idiosyncratic adverse effects in humans: peptic ulcer, stomatitis, hepatitis, nephritis, aplastic anemia, leukopenia, agranulocytosis and thrombocytopenia. Phenylbutazone-associated fatalities have occurred after the appearance of GI distress, convulsions, metabolic acidosis, hepatic necrosis, and renal failure. Serious symptoms in adults developed after ingestions of 4 to 40 g; a 2 g injestion in a 1 yr old resulted in death.