Indications
Castor Oil is a natural oil pressed from the seeds of the castor plant. Taken by mouth it is a stimulant laxative for occasional constipation or for emptying the bowel before some medical procedures. On the skin and hair it is used as an emollient (moisturiser) for dry skin, lips and scalp, and as a base in some ointments and creams.
How It Works
In the gut, castor oil is broken down to ricinoleic acid, which irritates and stimulates the bowel wall, increasing movement and water in the bowel so that a bowel motion usually follows within 2 to 6 hours. On the skin it forms a thick, oily layer that reduces water loss and softens dry areas.
Dosage and Administration
As a laxative, the usual adult dose is 15 to 30 ml by mouth as a single dose, preferably on an empty stomach and not at bedtime because of its fast action, or as directed on the label. It may be mixed with juice to improve the taste. It is for short-term use only. Children should use it only as advised by a doctor. On the skin, apply a small amount to the affected area as needed.
Interactions
- Can reduce absorption of other medicines taken at the same time; separate by at least 2 hours.
- Diarrhoea from laxatives can lower potassium, increasing the risk of side effects with Digoxin and with diuretics or corticosteroids.
- Avoid using it with other laxatives unless advised.
Contraindications
- Pregnancy (it can trigger contractions of the womb).
- Bowel blockage, unexplained stomach pain, appendicitis, nausea or vomiting, and inflammatory bowel disease.
- Allergy to castor oil.
Side Effects
Taken by mouth it can cause stomach cramps, nausea, diarrhoea and, with overuse, dehydration and loss of salts. Regular long-term use can make the bowel dependent on laxatives. On the skin it is usually well tolerated but may cause irritation or rash in sensitive people.
Get urgent medical help if there is severe stomach pain, rectal bleeding, severe diarrhoea with dizziness or fainting, muscle weakness or irregular heartbeat, or swelling of the face and difficulty breathing.
Pregnancy and Lactation
Do not take castor oil by mouth during pregnancy, as it can cause contractions; do not use it to try to start labour without medical supervision. It is best avoided by mouth during breastfeeding unless a doctor advises. Use on the skin is generally considered acceptable.
Precautions and Warnings
- Do not use as a laxative for more than a few days; see a doctor if constipation persists or bowel habits change.
- Drink plenty of fluids when using it.
- Do a patch test before using on sensitive skin and avoid contact with the eyes.
- Never eat raw castor seeds, which contain a deadly poison; the refined oil does not.
Overdose
Too much can cause severe diarrhoea, cramps, dehydration and salt imbalance. Drink fluids and seek medical help if symptoms are severe.
Therapeutic Class
Stimulant laxative; emollient.
Storage
Store below 30°C in a tightly closed bottle, away from light. Keep out of the reach of children.
Prepared by the Oshud Alo team from standard drug references. For information only; always follow your doctor's advice.