Castor oil is used for constipation and bowel preparation prior to colonoscopy, childbirth, and many other conditions, but there is no good scientific evidence to support these uses.
The hull of the castor seed contains a deadly poison called ricin. This is why the hull must be removed before use. Ricin 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.
How does it work ?
Uses & Effectiveness ?
Possibly Effective for
- Emptying the colon before a colonoscopy. Taking a single dose of castor oil might be effective for emptying the colon. However, it does not seem to work as well as other bowel preparations, such as sodium phosphate or bisacodyl plus magnesium citrate. Castor oil is not recommended for people who are preparing for a colonoscopy.
- Constipation. Castor oil works as a stimulant laxative for reducing constipation when taken by mouth.
- Dry eye. Using eye drops containing castor oil might reduce symptoms in people with dry eyes.
- Childbirth. Taking a single 60 mL dose of castor oil might start labor within 24 hours in some women who are at their delivery date but have not gone into labor.
Insufficient Evidence for
- Birth control. Early research suggests that taking a single dose of castor seeds with the outer coat removed might prevent pregnancy for up to 8-12 months.
- Swelling and sores in the mouth. Early research shows that using a specific castor oil mouthwash (Perioquil) 4 times daily for up to 30 days can improve mouth sores in elderly people who have dentures.
- Skin disorders.
- Swelling (inflammation) of the middle ear.
- Softening cysts.
- Adhesive bowel obstruction.
- Bunions and corns.
- Promoting the flow of breast milk.
- Other conditions.
Castor seeds that have had the outer coat removed (hulled) are POSSIBLY SAFE when taken as a single dose.
Consuming the whole castor seed is UNSAFE. The outer coating (hull) of the castor seed contains a deadly poison called ricin. This outer coating can cause nausea, vomiting, diarrhea, abdominal pain, dehydration, shock, severe fluid and chemical disturbances, damage to the liver, kidney, and pancreas, and death. Chewing as few as 1-6 whole seeds can kill an adult.
When applied into the eye: Castor oil eye drops are POSSIBLY SAFE when used for up to 30 days.
Special Precautions and Warnings
There isn't enough reliable information to know if castor oil is safe to use when breast-feeding. Stay on the safe side and avoid use.
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.
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.
Water pills (Diuretic drugs) interacts with CASTOR BEAN
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.
Be cautious with this combination
- For constipation: 15 mL of castor oil is commonly used.
- For emptying the colon before a colonoscopy: 15-60 mL of castor oil given 16 hours before the procedure.
- For 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.
- For emptying the colon before a colonoscopy: For children younger than 2 years, 1-5 mL is commonly used. For children 2-11 years of age, 5-15 mL is typically used. The dose for children over 12 is 15-60 mL given 16 hours before the procedure.
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