Castor is a plant that produces seeds (beans). Castor oil is produced by pressing ripe seeds that have had their outer covering (hull) removed. The hull contains a deadly poison called ricin. Castor oil has been used as medicine for centuries.
Castor seeds without the hull are used for birth control, constipation, leprosy, and syphilis.
Castor oil is used as a laxative for constipation, to start labor in pregnancy, and to start the flow of breast milk.
Some people apply castor seed paste to the skin as a poultice for inflammatory skin disorders, boils, carbuncles, pockets of infection (abscesses), inflammation of the middle ear, and migraineheadaches.
Castor oil is used topically to soften skin, bunions and corns; and to dissolve cysts, growths, and warts. It is also applied to the skin for osteoarthritis. Some women put castor oil inside the vagina for birth control or to cause an abortion. Castor oil is used in the eyes to soothe membranes irritated by dust or other materials.
In manufacturing, castor seeds are used to make paints, varnishes, and lubricating oils.
Ricin from the hull of the castor seed has been tested as a chemical warfare agent. Weapons-grade ricin is purified and produced in particles that are so small they can be breathed in. The smaller the particle size, the more poisonous the ricin. You may remember that ricin was found in letters sent to some Congress members and the White House, and in the possession of people linked to terrorist and antigovernment groups.
How does it work?
Castor seed is used to make castor oil, which is a strong laxative. In pregnancy, castor oil might start labor by stimulating the uterus.
Possibly Effective for:
- Constipation. Castor oil works as a stimulant laxative for reducing constipation.
- Birth control. There is some evidence that a single dose of seeds with the outer coat removed (hulled) can work as a contraceptive for up to 8-12 months.
- Stimulating full-term labor in pregnant women. A single 60 mL dose of castor oil appears to start labor within 24 hours in at least half of women at term pregnancy who try it. There is also some evidence that women at term pregnancy whose “water has broken” are more likely to go into labor and are less likely to need a Cesarean section if they take castor oil.
- Skin disorders.
- Swelling (inflammation) of the middle ear.
- Softening cysts.
- Adhesive bowel obstruction.
- Bunions and corns.
- Promoting the flow of breast milk.
- Other conditions.
Side Effects & Safety
Castor oil seems to be safe for most people when used short-term. In some people, castor oil can cause stomach discomfort, cramping, nausea, and faintness. Castor oil might also cause fluid and potassium loss from the body, especially when used for more than a week or in doses of more than 15-60 mL per day.
Although castor oil might be safe when used for starting labor in pregnant women at term, it should not be used without the supervision of a healthcare professional. It is UNSAFE to use in pregnant women who are not at term since it might bring on labor too early.
The whole seed is UNSAFE to take by mouth. The outer coating (hull) of the castor seed contains a deadly poison. This outer coating can cause nausea; vomiting; diarrhea; abdominal pain; dehydration; shock; blood cell destruction; severe fluid and chemical disturbances; liver, kidney, and pancreas damage; and death. Chewing as few as 1-6 whole seeds can kill an adult. If the seed is swallowed whole, poisoning is less likely; however, prompt medical attention is still an absolute necessity.
Not enough is known about the safety of applying castor oil or seed paste to the skin.
Special Precautions & Warnings:Children: Castor oil might be safe when taken by mouth in appropriate doses short-term. But taking castor oil for more than one week or taking more than the typical children's dose of 1-15 mL per day, depending on age, can cause a chemical imbalance in the body. Of course, all the warnings against chewing or swallowing whole seeds apply to children as well as adults.
Pregnancy: Using castor oil in pregnant women at term (ready to deliver) seems to be safe. Midwives routinely use castor oil for starting labor in pregnant women who are ready to deliver. However, castor oil should not be used for this purpose without the supervision of a healthcare provider. Pregnant women who are not at term should not use castor oil because it might start labor early and cause a miscarriage. Do not chew or swallow whole seeds. Serious health effects, including death, can occur.
Don’t take castor oil if you are breast-feeding. Not enough research has been done to know whether a mother’s use of castor oil is safe for nursing infants.
Intestinal problems: Don’t use castor oil if you have a blocked intestine, unexplained stomach pain, or problems with your bile ducts or gall bladder.
Moderate Interaction Be cautious with this combination
- Water pills (Diuretic drugs) interacts with CASTOR
Castor oil is a laxative. Some laxatives can decrease potassium in the body. "Water pills" can also decrease potassium in the body. Taking castor oil along with "water pills" might decrease potassium in the body too much.
Some "water pills" that can decrease potassium include chlorothiazide (Diuril), chlorthalidone (Thalitone), furosemide (Lasix), hydrochlorothiazide (HCTZ, HydroDIURIL, Microzide), and others.
The following doses have been studied in scientific research:
- For constipation: 15 mL of castor oil is commonly used.
- For cleaning the bowel before surgery or examining the colon (colonoscopy): The dose for adults and children over 12 is 15-60 mL of castor oil given 16 hours before the procedure. For children age 2-11 years, 5-15 mL is typically used. In children younger than 2 years, 1-5 mL is commonly used.
- For starting childbirth: A variety of dosage schedules have been used. Single doses vary from 5-120 mL of castor oil. A one-time dose of 60 mL in fruit juice is commonly used. Other dosing schedules that have been used include 5 mL in peppermint tea every 2 hours, 15 mL three times daily, 30 mL every 2 hours, 30 mL every 6 hours, 30 mL every 3 hours for 3 doses, 60 ml daily, and 60 mL daily for 2 days.