There is a "use on pet" option which increases the stats of your chosen pet. However, there's another option to "use item" and I'm afraid to try it! Does anyone know what happens when you choose this option?
It will generate more of the other throwing vials that the Golum drops, the potions you can use in battle. I wish they would remove the option because those throwing vials are much more common and cheaper than the stat booster. Unless there is an achievement for using the option I'm not aware of.