Castor

woman with abdominal pain

What other names is Castor Bean known by?

African Coffee Tree, Arandi, Bi Ma Zi, Bofareira, Castorbean, Castor Bean, Castor Bean Plant, Castor Oil, Castor Oil Plant, Castor Seed, Erand, Eranda, Gandharva Hasta, Graine de Ricin, Huile de Ricin, Huile de Ricin Végétale, Mexico Weed, Palma Christi, Ricin, Ricin Commun, Ricin Sanguin, Ricine, Ricino, Ricinus communis, Ricinus sanguines, Tangantangan Oil Plant, Wonder Tree.

What is Castor Bean?

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 migraine headaches.

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.

Possibly Effective for...

  • Bowel preparation before colonoscopy. Some research suggests that taking a single dose of castor oil is effective for bowel preparation in people undergoing a colonoscopy. However, castor oil might not be as effective as other bowel preparations, such as sodium phosphate or bisacodyl plus magnesium citrate.
  • Constipation. Castor oil works as a stimulant laxative for reducing constipation when taken by mouth.
  • Birth control. There is some evidence that a single dose of castor seeds with the outer coat removed (hulled) can work as a contraceptive for up to 8-12 months.
  • Dry eyes. Some research suggests that using eye drops containing castor oil might be effective for people with dry eyes.
  • 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.

Insufficient Evidence to Rate Effectiveness for...

  • Syphilis.
  • Arthritis.
  • Skin disorders.
  • Boils.
  • Blisters.
  • Swelling (inflammation) of the middle ear.
  • Migraines.
  • Softening cysts.
  • Adhesive bowel obstruction.
  • Warts.
  • Bunions and corns.
  • Promoting the flow of breast milk.
  • Other conditions.
More evidence is needed to rate the effectiveness of castor for these uses.

Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).

Quick GuideDigestive Disorders: Common Misconceptions

Digestive Disorders: Common Misconceptions

How does Castor Bean work?

Castor bean is used to make castor oil, which is a strong laxative. In pregnancy, castor oil might start labor by stimulating the uterus.

Are there safety concerns?

Castor oil is LIKELY SAFE for most people when taken by mouth as a single dose. In some people, castor oil can cause stomach discomfort, cramping, nausea, and faintness.

Castor oil seeds that have had the outer coat removed (hulled) are POSSIBLY SAFE when taken by mouth as a single dose. Also, castor oil eye drops are POSSIBLY SAFE when applied to the eye for up to 30 days.

Castor oil is POSSIBLY UNSAFE when taken by mouth long-term or in large doses. It might cause fluid and potassium loss from the body when used for more than a week or in doses of more than 15-60 mL per day.

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.

Special Precautions & Warnings:

Children: Castor oil is POSSIBLY SAFE when taken by mouth in appropriate doses short-term (less than one week). Castor oil is POSSIBLY UNSAFE when taken by mouth for more than one week or at a high dose. 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. Castor seeds are UNSAFE if the whole seed is taken by mouth.

Pregnancy and breast-feeding: Using castor oil in pregnant women at term (ready to deliver) is POSSIBLY 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. Also, it is LIKELY UNSAFE to use castor oil in pregnant women who are not at term. It might bring on labor too early. It is UNSAFE for women who are pregnant to take whole castor seeds by mouth, as it can cause serious toxic effects or death.

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.

Are there any interactions with medications?



Water pills (Diuretic drugs)
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.

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.

Dosing considerations for Castor Bean.

The following doses have been studied in scientific research:

BY MOUTH:
  • 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.
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Reviewed on 3/29/2011 12:35:40 PM

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