Castor oi packs are marvelous! I used them for months and months and couldn't have gotten along without them. The castor oil has the frequency of sunshine. It will help to heal the bile duct as there is an awful lot of junk that passes through it while you're emptying your liver of garbage over time. They take away a LOT of the pain and help heal the liver. They get the bugs out of hiding, too. Just a whole lot messy, that's all. If you use them, you know to use old bedding and old clothes and to cover your pack with some plastic bags that will protect your bedding and clothing. Use a heating pad over the pack. Keep the pack in the refridgerator for 30 days, adding some more castor oil to the pack each day you use it. Discard it after 30 days and make a new one.