What Is Peg-45 Hydrogenated Castor Oil?
Peg-45 Hydrogenated Castor Oil is a plant-derived ingredient that starts with castor oil pressed from the seeds of the Ricinus communis plant. The oil is first hydrogenated, which means hydrogen is added to make it more solid and stable. It is then reacted with about 45 units of ethylene oxide, giving it the PEG part of its name and turning it into a waxy, water-friendly substance.
Castor oil has been used for skin and hair care for generations. Chemists began modifying it in the mid-20th century to improve its texture and make it mix better with water. That process led to a family of ingredients called PEG hydrogenated castor oils, with the number showing how many ethylene oxide units are attached. The 45-unit version offers a good balance of thickness and ease of blending, so it became popular in modern formulations.
Making Peg-45 Hydrogenated Castor Oil starts with refined castor oil. The oil is hydrogenated under heat and pressure, then cooled and combined with ethylene oxide in a controlled setting. The finished ingredient is purified, tested for quality and supplied as flakes or a soft solid.
You will most often find Peg-45 Hydrogenated Castor Oil in facial cleansers, micellar waters, makeup removers, shampoos, conditioners, moisturizers, sheet masks and occasional anti-aging creams. It can also appear in serums or spot treatments where a gentle cleansing boost or stable emulsion is needed.
Peg-45 Hydrogenated Castor Oil’s Cosmetic Benefits/Uses
This versatile ingredient brings two main strengths to a formula
- Cleansing: Its water-loving and oil-loving parts let it grab onto dirt, makeup and excess sebum, then rinse them away with water. This helps products leave skin or hair feeling clean yet comfortable
- Emulsifying: It acts like a glue that holds oil and water together, giving creams, lotions and washes a smooth, even texture that does not split in the bottle or on your skin
Who Can Use Peg-45 Hydrogenated Castor Oil
Peg-45 Hydrogenated Castor Oil is considered gentle enough for most skin types. Normal, oily and combination skin usually benefit from its light cleansing action while dry or sensitive skin generally tolerate it well because it is less stripping than stronger surfactants. Those with a known allergy to castor derivatives should steer clear, but such reactions are rare.
The ingredient is plant derived and contains no animal by-products so it is suitable for vegans and vegetarians.
Current safety data show no specific risks for pregnant or breastfeeding women when this ingredient is used in rinse-off or leave-on cosmetics. This is not medical advice and anyone who is pregnant or nursing should discuss any skincare product with a doctor to be on the safe side.
Peg-45 Hydrogenated Castor Oil does not make skin more sensitive to sunlight and it has no known interactions with common topical actives. It is also fragrance free and colorant free which reduces the chance of extra sensitivities.
Potential Side Effects/Adverse Reactions
Side effects from topical Peg-45 Hydrogenated Castor Oil vary from person to person. The points below list potential reactions that could occur, though most users will not experience them when the ingredient is formulated and used correctly.
- Skin irritation – mild redness or stinging can occur in very sensitive skin or if used at high concentrations
- Allergic contact dermatitis – rare but possible in individuals allergic to castor oil derivatives
- Eye irritation – may cause temporary discomfort if a cleanser or makeup remover gets into the eyes
- Follicular buildup – extremely acne-prone users might notice clogged pores if the formula is not thoroughly rinsed
If you notice any of these effects discontinue use and consult a healthcare professional or dermatologist.
Comedogenic Rating
Rating: 1 out of 5
Peg-45 Hydrogenated Castor Oil is largely water soluble thanks to its PEG groups, which means it tends to rinse away instead of lingering and clogging pores. It is also used at modest levels in most formulas and is often combined with other mild surfactants that help it wash off cleanly. For these reasons it sits low on the comedogenic scale.
Suitable for most acne-prone users, though extremely sensitive or easily congested skin should still monitor how it reacts.
As with any cleansing agent, residue left on the skin can raise the risk of clogged pores, so thorough rinsing is always a good idea.
Summary
Peg-45 Hydrogenated Castor Oil works mainly as a gentle cleanser and an emulsifier. Its dual water-loving and oil-loving structure lifts away dirt then keeps oils and water mixed so products stay smooth and stable.
The ingredient is fairly common in cleansers, micellar waters and light creams though it is not as famous as some newer surfactants. Formulators like it because it is plant derived, versatile and easy to work with.
Current research shows it is safe for most skin types with a very low chance of irritation or pore blockage. Still, every skin is different so patch testing a new product is a smart move before adding it to your daily routine.