Castor Oil
Castor oil: what a Cochrane review found for labor induction, what a systematic review says about hair, and why swallowing it is not a safe home remedy.
Content last updated . This page has not been medically reviewed.
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Overview and identity
Castor oil is a fixed oil from the castor bean. It is a potent cathartic (strong laxative). [1] Searches focus on hair growth, packs and constipation. This page reports what we could source.What the research shows
| Use | What the research shows | Strength |
|---|---|---|
| Labor induction (swallowed) | A Cochrane review of 3 small trials (233 women) found no evidence of differences in caesarean rates or other outcomes versus placebo or no treatment, and the numbers were too small to detect all but large differences. All women who swallowed castor oil felt nauseous. The trials were small, had methodological problems and used single doses. [1] | Very limited |
| Hair | A systematic review found weaker evidence that castor oil improves hair luster, and no strong evidence it improves hair growth or treats infestation. [2] | Weak |
| Constipation, packs | We found no source we could read, so we make no claim. | Not assessed |
Safety
Castor oil is a strong laxative, and nausea was universal in the labor trials. [1] Do not use it to try to start labor without a clinician, and do not swallow it as a "detox"; see Detox claims. We found no readable source on the other risks, so ask a pharmacist.
Frequently asked questions
Does castor oil induce labor?
A Cochrane review found no clear evidence of benefit from three small trials, and all women who swallowed it felt nauseous. [1]
Does castor oil make hair grow?
A systematic review found no strong evidence for hair growth. [2]
References
- Kelly AJ, Kavanagh J, Thomas J. Castor oil, bath and/or enema for cervical priming and induction of labour. Cochrane Database Syst Rev. 2013;(7):CD003099. PubMed 23881775.
- Phong C, et al. Coconut, Castor, and Argan Oil for Hair in Skin of Color Patients: A Systematic Review. J Drugs Dermatol. 2022;21(7):751-757. PubMed 35816075.