pet wellbeing - milk thistle for cats - natural support for feline liver health - 2oz (59ml) pet wellbeing pet wellbeing's canine milk thistle is all-natural, glycerine-based, and safe for cats. milk thistle should be administered to every cat taking liver taxing medications and especially if the liver is damaged. the active ingredients in milk thistle are known as silymarin, and these ingredients help maintain the health of your cat's liver, scavenge for harmful free radicals, help guard against toxins trying to bind to the cat's liver, and support the stability of liver membranes. as an anti-oxidant, silymarin is even more effective than vitamin e. it also helps support the production of new liver cells in cats.