Castor Oil
HerbalAlso called · 4 names▾▴
castor, castor bean oil, castor seed oil, Ricinus communis
Herbal laxative and oil
Herbs and supplements are not FDA-approved before sale. About these sources
- Other
- Topical
Research strength: 1 / 5
EMA's 2016 herbal monograph states that use during pregnancy is contraindicated because castor oil can influence labor. MotherToBaby identifies castor oil as a stimulant laxative and says it can cause severe bowel and uterine cramping. MotherToBaby reports that studies have not tested whether laxatives increase miscarriage risk, and its birth-defect information is about laxatives as a group rather than castor oil specifically. Human studies of castor oil for labor induction enrolled people near term, so they do not tell us about use earlier in pregnancy. Ask your provider about your situation.
Last reviewed: 2026-10-16
Research strength: 1 / 5
EMA's 2016 herbal monograph states that use during pregnancy is contraindicated because castor oil can influence labor. MotherToBaby identifies castor oil as a stimulant laxative and says it can cause severe bowel and uterine cramping. MotherToBaby reports that studies have not tested whether laxatives increase miscarriage risk, and its birth-defect information is about laxatives as a group rather than castor oil specifically. Human studies of castor oil for labor induction enrolled people near term, so they do not tell us about use earlier in pregnancy. Ask your provider about your situation.
Last reviewed: 2026-10-16
Research strength: 3 / 5
EMA's 2016 herbal monograph states that use during pregnancy is contraindicated because castor oil can influence labor. MotherToBaby reports that castor oil can cause severe diarrhea and bowel and uterine cramping, though contractions are unlikely to start labor if the cervix is not ready. Cochrane found too little evidence to judge labor induction and reported nausea in everyone who ingested castor oil in its included trials, while a 2022 review and a 2026 randomized trial found labor began more often after oral castor oil. A 2026 hospital study recorded one complete uterine rupture and one dehiscence after castor-oil-cocktail induction in people with a prior cesarean, but its design cannot establish that the cocktail caused them; the authors say not to use it outside a hospital. ACOG describes clinician-led induction methods but does not mention castor oil; the studies tested ingestion, an enema, or a bath, not skin packs. Ask your provider about your situation.
Last reviewed: 2026-10-16
Sources
- EMA: European Union herbal monograph on Ricinus communis L., oleumEU agencyEuropean guidance
- MotherToBaby: LaxativesTeratology service
- Kelly et al., Cochrane Review: Castor oil, bath and/or enema for cervical priming and induction of labourResearch review
- Amerizadeh et al., 2022 systematic review and meta-analysisUS government
- Odoh et al., 2026 randomized controlled trialUS government
- Jakubowski et al., 2026 retrospective cohortUS government
- ACOG: Labor InductionProfessional society
Castor Oil — Breastfeeding
Research strength: 1 / 5
EMA's herbal monograph states that use during lactation is contraindicated because castor oil may pass into breast milk. LactMed says there are no data on castor-oil components in milk or their effects in nursing parents or infants; because information is lacking, it says other laxatives may be preferred. MotherToBaby says the amount of most laxatives passing into milk is usually low, but it does not give castor-oil-specific milk data. LactMed says castor oil given directly to newborns should be avoided; that is a different exposure from use by a breastfeeding parent. LactMed reports no valid trials for using castor oil to increase milk supply and says a milk-supply aid does not replace evaluation and counseling about factors that affect milk production. Ask your provider about your situation.
Last reviewed: 2026-10-16
Pregnancy
Cochrane's 2013 review included 3 trials and 233 women; it found too little evidence to determine effects on cervical ripening or labor induction, and it reported nausea in all women who ingested castor oil in the trials. Amerizadeh et al. (2022) included 12 studies and 1,653 pregnant women and reported more labor induction in the castor-oil groups than controls (RR 3.27, 95% CI 1.96 to 5.46); the authors noted that none of the included studies reported serious harms. Odoh et al. (2026) randomized 210 women at 40+0 to 41+0 weeks among membrane sweeping, castor oil, and control; labor within 48 hours occurred in 37/70 (52.9%) after castor oil and 17/70 (24.3%) in the control group, and the authors said larger studies were needed to confirm maternal and newborn safety. Jakubowski et al. (2026) retrospectively compared 824 castor-oil-cocktail inductions with 191 standard inductions in a university hospital. Additional induction was needed in 50.5% and 37.2%, respectively, with no significant group difference in delivery mode or maternal/fetal complications. In the 105-person trial-of-labor-after-cesarean subgroup, the paper recorded two uterine ruptures after castor-oil-cocktail inductions, one complete and one dehiscence; it says the subgroup was underpowered for this rare outcome and that causal conclusions cannot be drawn. The study authors say castor oil should not be used for labor induction outside a hospital. EMA's 2016 monograph contraindicates pregnancy use because castor oil can influence labor. A 2012 laboratory and mouse study found ricinoleic acid activated EP3 receptors and caused uterine contraction in mice; this mechanism does not establish early-pregnancy outcomes in humans.
Breastfeeding
LactMed's revision dated December 15, 2024 says no data were found on castor plant or castor-oil components in breast milk or on effects in nursing parents or infants, and says little of the active ricinoleic acid is thought to be absorbed from the intestine. MotherToBaby's April 1, 2026 laxatives sheet says the amount of most laxatives passing into breast milk is usually low, but it does not provide castor-oil-specific milk data. LactMed reports adverse effects after castor oil was given directly to newborns, including paralytic ileus and aspiration pneumonia, and a case of severe hypoalbuminemia in an infant given oil daily from the fifth day of life. These reports concern direct dosing, not transfer through breast milk. A 1989 survey of 274 lactating mothers in rural Karnataka reported that 9.72% used castor oil as a prelacteal feed; the survey described feeding practices, not effects of maternal use during breastfeeding. No human milk-transfer study was identified in the reviewed sources.
LactMed says pressing castor beans produces castor oil and purification removes ricin and ricine. It describes the oil as a strong stimulant laxative, with triglycerides mostly consisting of ricinoleic-acid esters. EMA notes that intestinal lipases release ricinoleic acid from castor oil. A 2012 laboratory and mouse study linked ricinoleic acid to EP3 prostanoid receptors and uterine smooth-muscle contraction in mice.
What was tested
The pregnancy studies concern oral castor oil, enemas, baths, or oral induction cocktails near term. Cochrane's included trials used single doses. The 2026 Enugu randomized trial used oral castor oil at 40+0 to 41+0 weeks. The 2026 Tübingen cohort used a 20 mL castor-oil cocktail with almond butter, apricot juice, cinnamon, and sparkling wine or water in a hospital setting. These studies do not test topical castor-oil skin packs. LactMed describes direct dosing of newborns separately from maternal use during breastfeeding; human breast-milk levels have not been reported in the reviewed sources.
Castor oil to start labor near term
- Source A says
- Cochrane found too little evidence to determine effects on cervical ripening or labor induction, and reported nausea in every woman who ingested castor oil in the included trials. (Kelly et al., Cochrane Review: Castor oil, bath and/or enema for cervical priming and induction of labour)
- Source B says
- A 2022 meta-analysis found higher labor induction in the castor-oil groups, and a 2026 randomized trial found more labor within 48 hours after oral castor oil than after expectant management. (Amerizadeh et al., Effect and Safety of Castor Oil on Labor Induction and Prevalence of Vaginal Delivery: A Systematic Review and Meta-Analysis, Odoh et al., Effectiveness of Membrane Stripping Versus Castor Oil for Induction of Labor in Prevention of Post-Term Pregnancy in Enugu: A Randomized Controlled Trial)
- Why they differ
- Cochrane searched through April 2013 and included three small trials with single doses and quality limits. The later studies added more participants, but used different methods and formulations. The 2026 cohort was retrospective, its comparison group was unmatched, and its cocktail included several ingredients besides castor oil.
- Other sources
- EMA's monograph contraindicates use during pregnancy because castor oil can influence labor. ACOG describes clinician-led induction methods but does not discuss castor oil. (EMA: European Union herbal monograph on Ricinus communis L., oleum, ACOG: Labor Induction)
- What the evidence shows overall
- Term studies suggest oral castor oil can increase labor onset, but the evidence does not establish better maternal or newborn outcomes. The 2026 hospital cohort recorded two uterine ruptures after castor-oil-cocktail inductions in people with prior cesareans, but it cannot establish causation and was underpowered for this rare outcome. These results do not establish effects earlier in pregnancy or of topical skin packs.
Castor oil during breastfeeding
- Source A says
- EMA says use during lactation is contraindicated because castor oil may pass into breast milk. (EMA: European Union herbal monograph on Ricinus communis L., oleum)
- Source B says
- LactMed reports no data on castor-oil components in milk or their effects in nursing parents or infants; it notes that little ricinoleic acid is thought to be absorbed and that other cathartics may be preferred because information is lacking. (LactMed: Castor)
- Why they differ
- EMA applies a precaution based on possible transfer into milk. LactMed emphasizes that human transfer and infant-effect data are absent and notes limited intestinal absorption of the active acid; neither source provides a measured milk concentration.
- Other sources
- MotherToBaby says the amount of most laxatives passing into breast milk is usually low, but its sheet does not give castor-oil-specific milk-transfer data. (MotherToBaby: Laxatives)
- What the evidence shows overall
- Human milk-transfer data for castor oil were not found. Under R2, the lack of human data supports an insufficient rating, while EMA's contraindication should remain visible. LactMed's reports of direct dosing effects in newborns are a separate exposure and do not show that castor oil passes through breast milk.
- MotherToBaby says people with ongoing constipation during pregnancy can discuss treatment with their healthcare provider and notes that fluids, high-fiber foods, and regular exercise may help. (MotherToBaby: Laxatives)
- ACOG describes clinician-led induction methods, including medicines or devices for cervical ripening and oxytocin; its page does not discuss castor oil. (ACOG: Labor Induction)
General research, not specific to pregnancy.
Castor oil is used as a stimulant laxative. LactMed reports adverse effects after direct dosing of newborns and says no valid trials support castor oil as a milk-supply aid.
- LactMed reports that direct castor-oil dosing in newborns has been associated with paralytic ileus and aspiration pneumonia, and separately describes severe hypoalbuminemia after daily dosing. These reports concern direct infant dosing, not exposure through breast milk. (LactMed: Castor)
- LactMed says no scientifically valid clinical trials support castor oil's reported uses to increase milk supply, and says evaluation and counseling about factors affecting milk production remain important. (LactMed: Castor)
- MotherToBaby: Herbal ProductsTeratology serviceSecondary
- MotherToBaby: LaxativesTeratology serviceSecondaryPage dated 2026-04-01Independent check
- LactMed: CastorUS governmentSecondaryPage dated 2024-12-15
- EMA: European Union herbal monograph on Ricinus communis L., oleumEU agencySecondaryPage dated 2016-02-02Independent checkEuropean guidance
- Kelly et al., Cochrane Review: Castor oil, bath and/or enema for cervical priming and induction of labourResearch reviewPrimaryPage dated 2013-07-24Independent check
- Amerizadeh et al., Effect and Safety of Castor Oil on Labor Induction and Prevalence of Vaginal Delivery: A Systematic Review and Meta-AnalysisUS governmentPrimary
- Odoh et al., Effectiveness of Membrane Stripping Versus Castor Oil for Induction of Labor in Prevention of Post-Term Pregnancy in Enugu: A Randomized Controlled TrialUS governmentPrimaryIndependent check
- Jakubowski et al., Castor Oil for Induction of Labor: A Large Retrospective Cohort Study in a University Hospital SettingUS governmentPrimaryIndependent check
- ACOG: Labor InductionProfessional societySecondaryIndependent check
- Tunaru et al., Castor oil induces laxation and uterus contraction via ricinoleic acid activating prostaglandin EP3 receptorsUS governmentPrimaryIndependent check
- Benakappa et al., Breast-feeding practices in rural Karnataka (India) with special reference to lactation failureUS governmentPrimary
Last reviewed 2026-10-16
Independent check 2026-10-16
Not yet clinician-reviewed
Ask your provider about your situation.
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