Castor oil (derived from Ricinus communis seeds) is a viscous, ricinoleic acid–rich oil used in skincare and cosmetics as an emollient, occlusive moisturizer, and solvent that softens skin and adds slip to formulations. It is also commonly used in lip products, cleansing oils, and as a carrier base.
| Reported effect | How often | Notes |
|---|---|---|
| Allergic contact dermatitis | Uncommon | Sensitization can occur, sometimes linked to ricinoleic acid, especially in lip cosmetics. |
| Skin irritation or redness | Uncommon | Mild irritation possible in sensitive individuals. |
| Acne or comedone formation | Uncommon | May be problematic for acne-prone skin in occlusive formulations. |
| Contact urticaria | Rare | Immediate hypersensitivity reactions rarely reported. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.
Peer-reviewed papers on this ingredient, via PubMed.