Castor oil is a vegetable oil obtained from the castor bean (technically castor seed as the castor plant, Ricinus communis,is not a member of the bean family). Castor oil (CAS number 8001-79-4) is a colorless to very pale yellow liquid with mild or no odor or taste. Castor oil penetrates deep into the skin thanks to its molecular weight, which is low enough to penetrate into the stratum corneum. Castor Isostearate Succinateis a polymeric mixture of esters with Isostearic Acid and Succinic Acid used for skin conditioning, such as in shampoo, lipstick and lip balm. Ricinoleic acid is the main component of castor oil and it exerts anti-inflammatory effects.
Castor oil and its derivatives have applications in the manufacturing of soaps, lubricants, hydraulic and brake fluids, paints,dyes, coatings, inks, cold resistant plastics, waxes and polishes, nylon, pharmaceuticals and perfumes. Sulfonated castor oil, also called sulfated castor oil, or Turkey Red Oil, is the only oil that completely disperses in water. It is made by adding sulfuric acid to pure castor oil. This allows easy use for making bath oil products. It was the first synthetic detergent after ordinary soap. It is used in formulating lubricants, softeners, and dyeing assistants. The United States Food and Drug Administration (FDA) has categorized castor oil as "generally recognized as safe and effective" (GRASE) for over-the-counter use as a laxative, with its major site of action the small intestine. However, although it maybe used for constipation, it is not a preferred treatment.
The use of cold pressed castor oil in folk medicine predates government medical regulations. Cold pressed castor oil is tasteless and odorless when pure. Uses include skin problems, burns, sunburns, skin disorders, skin cuts, and abrasions.
Castor oil has also been used to draw out styes in the eye by pouring a small amount into the eye and allowing it to circulate around the inside of the eyelid. Note that most bottles of castor oil indicate the oil is to be kept away from the eyes. The oil is also used as a rub or pack for various ailments, including abdominal complaints, headaches, muscle pains,inflammatory conditions, skin eruptions, lesions, and sinusitis.
A castor oil pack is made by soaking a piece of flannel in castor oil, then putting it on the area of complaint and placing a heat source, such as a hot water bottle, on top of it. This remedy was often suggested by the American psychic Edgar Cayce, given in many healing readings in the early mid-1900s. Castor oil has also been noted for its acne-healing abilities. In south Egypt, women use a large spoonful dosage of castor oil to prevent pregnancy for one year. It has also been claimed that castor promotes eyelash growth, however there's no supporting scientific data for any of these claims.