While controlled studies demonstrating efficacy and a standardized form and concentration of silymarin are lacking, it is being used to treat a variety of liver diseases in humans and domestic companion animals (birds, dogs, cats, horses, rabbits). It is mostly of interest in treating chronic and acute liver disease, cirrhosis, and as a hepatoprotective agent when hepatotoxic agents are ingested (e.g., Aminita phalloide; “Death Cap Mushrooms”).