You can use castor oil externally on your hair, eyelashes, and eyebrows to promote growth and hydration; on your skin for hydration, purification, and regeneration; on your nails to strengthen them and condition the cuticles; and for therapeutic castor oil packs (with wool flannel and a hot water bottle – 100% natural rubber or eco thermoplastic for those with rubber/latex sensitivities) for a variety of health issues. When using castor oil internally for constipation or to induce labor, the USP or pharmaceutical grade should be utilized.