At ORY®, we believe you should know what’s in your products and why. This page lists the published research behind what we say about castor rosemary oil (castor oil with rosemary essential oil). Each section starts with our claim, then tells you how well the research supports it, then lists the sources so you can read them yourself.
Please note: Some studies on this page tested rosemary for hair loss, which is a medical use. We share them for transparency. ORY® Castor Rosemary Oil is a cosmetic and is not intended to grow hair, prevent hair loss, or treat any condition.
How to read this page Supported — backed by peer-reviewed research or official safety reviews. Supported, with caveats — the research points this way, but mostly from laboratory or animal studies, or at different strengths than ORY® uses. Limited evidence — little or no published research yet. We say so openly. |
1. General Description and Role
Claim: Castor Rosemary Oil is an ORY® scalp blend of castor oil (usually 95–98%) with rosemary essential oil (2–5%) or rosemary-infused castor oil. It is diluted with a lighter oil before use. It helps the scalp feel refreshed and hair feel conditioned and glossy. |
Verification: Supported. The Cosmetic Ingredient Review (CIR) Expert Panel found castor seed oil safe as used and rosemary leaf oil safe when formulated to be non-sensitizing.
Citations:
- Cosmetic Ingredient Review Expert Panel. (2007). Final report on the safety assessment of Ricinus communis (castor) seed oil, hydrogenated castor oil, glyceryl ricinoleate, … and octyldodecyl ricinoleate. International Journal of Toxicology, 26(Suppl 3), 31–77 (reaffirmed in 2025). https://doi.org/10.1080/10915810701663150
- What it shows: CIR safety assessment of castor oil.
- Cosmetic Ingredient Review Expert Panel. (2018). Safety assessment of Rosmarinus officinalis (rosemary)-derived ingredients as used in cosmetics. International Journal of Toxicology, 37(3 Suppl), 12S–50S. https://doi.org/10.1177/1091581818800020
- What it shows: CIR safety assessment of rosemary ingredients.
- Cosmetic Ingredient Review Expert Panel. (2007). Final report on the safety assessment of Ricinus communis (castor) seed oil, hydrogenated castor oil, glyceryl ricinoleate, … and octyldodecyl ricinoleate. International Journal of Toxicology, 26(Suppl 3), 31–77 (reaffirmed in 2025). https://doi.org/10.1080/10915810701663150
2. Composition and Production
Claim: The blend combines castor oil (about 90% ricinoleic acid) with rosemary essential oil (rich in 1,8-cineole, camphor, and α-pinene) or with dried rosemary steeped in castor oil. ORY® recommends diluting 1 part blend with 2–4 parts jojoba or grape seed oil. |
Verification: Supported. Both components are well documented.
Citations:
- Cosmetic Ingredient Review Expert Panel. (2007). Final report on the safety assessment of Ricinus communis (castor) seed oil, hydrogenated castor oil, glyceryl ricinoleate, … and octyldodecyl ricinoleate. International Journal of Toxicology, 26(Suppl 3), 31–77 (reaffirmed in 2025). https://doi.org/10.1080/10915810701663150
- What it shows: Castor composition.
- Nieto, G., Ros, G., & Castillo, J. (2018). Antioxidant and antimicrobial properties of rosemary (Rosmarinus officinalis, L.): A review. Medicines, 5(3), 98. https://doi.org/10.3390/medicines5030098
- What it shows: Rosemary composition.
- Cosmetic Ingredient Review Expert Panel. (2007). Final report on the safety assessment of Ricinus communis (castor) seed oil, hydrogenated castor oil, glyceryl ricinoleate, … and octyldodecyl ricinoleate. International Journal of Toxicology, 26(Suppl 3), 31–77 (reaffirmed in 2025). https://doi.org/10.1080/10915810701663150
3. Skin Type Suitability
Claim: On skin, Castor Rosemary Oil is used only in limited ways, such as brow conditioning and oil cleansing. Sensitive skin should use the rosemary-infused version. |
Verification: Supported, with caveats. Rosemary essential oil can irritate or sensitize sensitive skin.
Citations:
- Cosmetic Ingredient Review Expert Panel. (2018). Safety assessment of Rosmarinus officinalis (rosemary)-derived ingredients as used in cosmetics. International Journal of Toxicology, 37(3 Suppl), 12S–50S. https://doi.org/10.1177/1091581818800020
- What it shows: Sensitization data.
- de Groot, A. C. (2020). Fragrances: Contact allergy and other adverse effects. Dermatitis, 31(1), 13–35. https://doi.org/10.1097/DER.0000000000000463
- What it shows: Fragrance allergy.
- Cosmetic Ingredient Review Expert Panel. (2018). Safety assessment of Rosmarinus officinalis (rosemary)-derived ingredients as used in cosmetics. International Journal of Toxicology, 37(3 Suppl), 12S–50S. https://doi.org/10.1177/1091581818800020
4. Hair and Scalp Suitability
Claim: In haircare, diluted Castor Rosemary Oil is massaged into the scalp to help it feel refreshed and to help hair feel conditioned. |
Verification: Limited evidence. In a 6-month trial in people with androgenetic alopecia, rosemary essential oil and 2% minoxidil produced similar hair counts, and a mouse study found rosemary leaf extract promoted regrowth. Castor oil has no controlled hair-growth evidence. These studies concern a medical condition; hair-growth and hair-loss claims, including for brows and lashes, are drug claims, and ORY® does not make them.
Citations:
- Panahi, Y., Taghizadeh, M., Marzony, E. T., & Sahebkar, A. (2015). Rosemary oil vs minoxidil 2% for the treatment of androgenetic alopecia: A randomized comparative trial. SKINmed, 13(1), 15–21. https://pubmed.ncbi.nlm.nih.gov/25842469/
- What it shows: Trial of rosemary oil in androgenetic alopecia (a medical use).
- Murata, K., et al. (2013). Promotion of hair growth by Rosmarinus officinalis leaf extract. Phytotherapy Research, 27(2), 212–217. https://pubmed.ncbi.nlm.nih.gov/?term=Promotion%20of%20hair%20growth%20by%20Rosmarinus%20officinalis%20leaf%20extract
- What it shows: Mouse study.
- U.S. Food and Drug Administration. 21 CFR 310.527 — Drug products offered over-the-counter for external use as hair growers or for hair loss prevention. https://www.law.cornell.edu/cfr/text/21/310.527
- What it shows: FDA treats hair-growth products as drugs.
- Panahi, Y., Taghizadeh, M., Marzony, E. T., & Sahebkar, A. (2015). Rosemary oil vs minoxidil 2% for the treatment of androgenetic alopecia: A randomized comparative trial. SKINmed, 13(1), 15–21. https://pubmed.ncbi.nlm.nih.gov/25842469/
5. Benefits
Claim: Castor Rosemary Oil helps the scalp feel refreshed and helps hair look glossy and feel conditioned. |
Verification: Supported, with caveats. Castor oil’s conditioning and rosemary’s fresh scent are well established. Anti-inflammatory and antimicrobial findings come from animal and lab studies of the separate components, and ORY® does not make those claims.
Citations:
- Vieira, C., Evangelista, S., Cirillo, R., Lippi, A., Maggi, C. A., & Manzini, S. (2000). Effect of ricinoleic acid in acute and subchronic experimental models of inflammation. Mediators of Inflammation, 9(5), 223–228. https://doi.org/10.1080/09629350020025737
- What it shows: Animal study of ricinoleic acid.
- Nieto, G., Ros, G., & Castillo, J. (2018). Antioxidant and antimicrobial properties of rosemary (Rosmarinus officinalis, L.): A review. Medicines, 5(3), 98. https://doi.org/10.3390/medicines5030098
- What it shows: Lab review of rosemary.
- Vieira, C., Evangelista, S., Cirillo, R., Lippi, A., Maggi, C. A., & Manzini, S. (2000). Effect of ricinoleic acid in acute and subchronic experimental models of inflammation. Mediators of Inflammation, 9(5), 223–228. https://doi.org/10.1080/09629350020025737
6. Use Across ORY® Product Lines
Claim: Castor Rosemary Oil is used mainly in ORY® Haircare, with limited use in Skincare, Handmade Soap, and Cosmetics. |
Verification: Supported. In the diluted product ORY® keeps rosemary essential oil at about 1–2%. FDA has not yet issued its fragrance allergen labeling rule (as of September 2026).
| Product line | Typical level | How ORY® uses it |
| Skincare | 10–30% in blends | Brow conditioning and oil-cleansing blends. |
| Haircare | 20–50% diluted with jojoba or grape seed | Scalp massage and pre-shampoo treatments. |
| Handmade Soap | 5–10% of oils | Shampoo and body bars. |
| Cosmetics | 10–30% | Brow gels. |
Citations:
- Cosmetic Ingredient Review Expert Panel. (2007). Final report on the safety assessment of Ricinus communis (castor) seed oil, hydrogenated castor oil, glyceryl ricinoleate, … and octyldodecyl ricinoleate. International Journal of Toxicology, 26(Suppl 3), 31–77 (reaffirmed in 2025). https://doi.org/10.1080/10915810701663150
- What it shows: Reported uses.
- U.S. Food and Drug Administration. Fragrance allergen labeling for cosmetics (MoCRA rulemaking, RIN 0910-AI90). As of September 2026, no proposed or final rule had been published. https://www.reginfo.gov/public/do/eAgendaViewRule?pubId=202404&RIN=0910-AI90
- What it shows: Fragrance allergen labeling status.
- U.S. Food and Drug Administration. Is It a Cosmetic, a Drug, or Both? (Or Is It Soap?) https://www.fda.gov/cosmetics/cosmetics-laws-regulations/it-cosmetic-drug-or-both-or-it-soap
- What it shows: FDA explains how soap is regulated.
- Cosmetic Ingredient Review Expert Panel. (2007). Final report on the safety assessment of Ricinus communis (castor) seed oil, hydrogenated castor oil, glyceryl ricinoleate, … and octyldodecyl ricinoleate. International Journal of Toxicology, 26(Suppl 3), 31–77 (reaffirmed in 2025). https://doi.org/10.1080/10915810701663150
7. Pros
Claim: A popular scalp-care ritual combining two CIR-reviewed ingredients. |
Verification: Supported. Well documented composition and long cosmetic use.
Citations:
- Cosmetic Ingredient Review Expert Panel. (2007). Final report on the safety assessment of Ricinus communis (castor) seed oil, hydrogenated castor oil, glyceryl ricinoleate, … and octyldodecyl ricinoleate. International Journal of Toxicology, 26(Suppl 3), 31–77 (reaffirmed in 2025). https://doi.org/10.1080/10915810701663150
- What it shows: Safety conclusion.
- Cosmetic Ingredient Review Expert Panel. (2018). Safety assessment of Rosmarinus officinalis (rosemary)-derived ingredients as used in cosmetics. International Journal of Toxicology, 37(3 Suppl), 12S–50S. https://doi.org/10.1177/1091581818800020
- What it shows: Safety conclusion.
- Cosmetic Ingredient Review Expert Panel. (2007). Final report on the safety assessment of Ricinus communis (castor) seed oil, hydrogenated castor oil, glyceryl ricinoleate, … and octyldodecyl ricinoleate. International Journal of Toxicology, 26(Suppl 3), 31–77 (reaffirmed in 2025). https://doi.org/10.1080/10915810701663150
8. Cons
Claim: The blend is thick, rosemary oil can irritate or sensitize, and neither ingredient is proven to grow hair in cosmetic use. |
Verification: Supported. We list these limits so you have the full picture:
- Thick. Must be diluted.
- Rosemary cautions. Camphor-rich; aromatherapy guidance advises caution in pregnancy, epilepsy, and young children.
- Allergy. Rosemary oil contains fragrance allergens.
- No growth claims. Medical-use studies cannot support cosmetic hair-growth claims.
- Buildup. Rinse thoroughly.
Citations:
- de Groot, A. C. (2020). Fragrances: Contact allergy and other adverse effects. Dermatitis, 31(1), 13–35. https://doi.org/10.1097/DER.0000000000000463
- What it shows: Fragrance allergy.
- Panahi, Y., Taghizadeh, M., Marzony, E. T., & Sahebkar, A. (2015). Rosemary oil vs minoxidil 2% for the treatment of androgenetic alopecia: A randomized comparative trial. SKINmed, 13(1), 15–21. https://pubmed.ncbi.nlm.nih.gov/25842469/
- What it shows: Medical-use study.
- de Groot, A. C. (2020). Fragrances: Contact allergy and other adverse effects. Dermatitis, 31(1), 13–35. https://doi.org/10.1097/DER.0000000000000463
9. Safety Notes
Claim: Patch test before use; for external use only. |
Verification: Supported. Follow these precautions:
- Patch test any new product on a small area for 24–48 hours before full use.
- Always dilute before use on the scalp.
- If you are pregnant, nursing, have epilepsy, or are buying for a child, ask a healthcare provider before use.
- Keep away from the eyes, even in brow products.
- Store away from heat and light, and discard if it smells rancid.
- Stop use if redness, burning, itching, or rash occurs, and talk to a healthcare provider.
- For external use only. Avoid the eyes.
- If you are pregnant, nursing, have a medical condition, or are buying for a child, ask a healthcare provider before use.
Citations:
- de Groot, A. C. (2020). Fragrances: Contact allergy and other adverse effects. Dermatitis, 31(1), 13–35. https://doi.org/10.1097/DER.0000000000000463
- What it shows: Fragrance allergy.
- Cosmetic Ingredient Review Expert Panel. (2018). Safety assessment of Rosmarinus officinalis (rosemary)-derived ingredients as used in cosmetics. International Journal of Toxicology, 37(3 Suppl), 12S–50S. https://doi.org/10.1177/1091581818800020
- What it shows: Safety data.
- de Groot, A. C. (2020). Fragrances: Contact allergy and other adverse effects. Dermatitis, 31(1), 13–35. https://doi.org/10.1097/DER.0000000000000463
10. Product-line notes
- ORY® Skincare: For external use only. Not for deep or puncture wounds, animal bites, or serious burns.
- ORY® Haircare: Designed for scalp comfort and the look and feel of hair. Not intended to treat dandruff or scalp conditions, or to promote hair growth or prevent hair loss. If you notice sudden shedding or a persistent itchy, flaking scalp, see a dermatologist.
- ORY® Handmade Soap: Handmade soap is naturally alkaline, and each bar may vary slightly in color, scent, and texture. Not intended to treat eczema or any skin condition.
- ORY® Cosmetics: Lip products are not intended to treat or protect chapped or cracked lips. Do not share applicators, and replace any product that changes color, smell, or texture.
11. References
Peer-reviewed research
- Cosmetic Ingredient Review Expert Panel. (2007). Final report on the safety assessment of Ricinus communis (castor) seed oil, hydrogenated castor oil, glyceryl ricinoleate, … and octyldodecyl ricinoleate. International Journal of Toxicology, 26(Suppl 3), 31–77 (reaffirmed in 2025). https://doi.org/10.1080/10915810701663150
- Cosmetic Ingredient Review Expert Panel. (2018). Safety assessment of Rosmarinus officinalis (rosemary)-derived ingredients as used in cosmetics. International Journal of Toxicology, 37(3 Suppl), 12S–50S. https://doi.org/10.1177/1091581818800020
- de Groot, A. C. (2020). Fragrances: Contact allergy and other adverse effects. Dermatitis, 31(1), 13–35. https://doi.org/10.1097/DER.0000000000000463
- Murata, K., et al. (2013). Promotion of hair growth by Rosmarinus officinalis leaf extract. Phytotherapy Research, 27(2), 212–217. https://pubmed.ncbi.nlm.nih.gov/?term=Promotion%20of%20hair%20growth%20by%20Rosmarinus%20officinalis%20leaf%20extract
- Nieto, G., Ros, G., & Castillo, J. (2018). Antioxidant and antimicrobial properties of rosemary (Rosmarinus officinalis, L.): A review. Medicines, 5(3), 98. https://doi.org/10.3390/medicines5030098
- Panahi, Y., Taghizadeh, M., Marzony, E. T., & Sahebkar, A. (2015). Rosemary oil vs minoxidil 2% for the treatment of androgenetic alopecia: A randomized comparative trial. SKINmed, 13(1), 15–21. https://pubmed.ncbi.nlm.nih.gov/25842469/
- Vieira, C., Evangelista, S., Cirillo, R., Lippi, A., Maggi, C. A., & Manzini, S. (2000). Effect of ricinoleic acid in acute and subchronic experimental models of inflammation. Mediators of Inflammation, 9(5), 223–228. https://doi.org/10.1080/09629350020025737
Government and regulatory sources
- U.S. Food and Drug Administration. 21 CFR 310.527 — Drug products offered over-the-counter for external use as hair growers or for hair loss prevention. https://www.law.cornell.edu/cfr/text/21/310.527
- U.S. Food and Drug Administration. Fragrance allergen labeling for cosmetics (MoCRA rulemaking, RIN 0910-AI90). As of September 2026, no proposed or final rule had been published. https://www.reginfo.gov/public/do/eAgendaViewRule?pubId=202404&RIN=0910-AI90
- U.S. Food and Drug Administration. Is It a Cosmetic, a Drug, or Both? (Or Is It Soap?) https://www.fda.gov/cosmetics/cosmetics-laws-regulations/it-cosmetic-drug-or-both-or-it-soap
