Absolutely! I have been doing castor oil packs for years and often recommend them for those who are cleansing. Castor oil pulls toxins and other impurities through the skin. You can put the castor oil pack on any part of the body that may be injured or aching, and putting it over the liver is recommended for cleansing.
There is a book called "The Oil that Heals" written by Dr. William McGarey who founded the ARE clinic. You will find it fascinating.
To do a castor oil pack you will need to castor oil, a heating pad, a large piece of wool flannel or cotton flannel, some towels, and some large plastic sheets such as a garbage bag. The plastic is used to protect your bed or whatever other furniture you are going to lay on, and to protect the heating pad in case any oil drips down. The oil is pretty thick and will stain fabrics.
When you buy the wool flannel, it has instructions on how to do the pack. It is recommended that you lay still for about an hour with the castor oil pack over the liver area, so that means you'll need some down time. You should read or be peaceful during this time, so it's also a great stress reducer!