The pack is just as important as the oil. The castor oil pack ensures that the castor oil deeply permeates the tissues. It’s also what produces the neurological switch into the parasympathetic state and stimulates a vast amount of beneficial neurohormones like oxytocin and dopamine. If you use the oil on your body without the pack, you will lose much of the relaxation benefit. A castor oil pack is simply a way to apply castor oil to the skin, like you would do with a medicated wrapping.
Applying the pack on the body stimulates the sensory receptors in your skin. This sends a message via the somatic-visceral reflexes to the organs inside the body. The corresponding organs are the liver, pancreas, stomach, small, large, kidneys, and adrenals.