What Is Poloxamer 238?
Poloxamer 238 is a synthetic, non-ionic surfactant made by linking blocks of ethylene oxide and propylene oxide in a precise sequence. Chemically it is described as oxirane, methyl-, polymer with oxirane (97;39), wording that reflects the ratio of its building blocks. Because it is produced entirely in the lab rather than harvested from plants or animals, supply is consistent and free of common allergens like nuts or soy.
The poloxamer family was introduced in the 1960s when chemists were searching for gentler alternatives to soap-based detergents. Over time formulators noticed that certain poloxamers could not only lift away dirt but also help oil and water stay mixed, a combination ideal for personal care products. Poloxamer 238 sits in the middle of the series, balancing cleansing power with a milder skin feel, which explains its popularity in modern cosmetics.
Manufacturing starts with propylene oxide, which is first polymerized to form a hydrophobic core. Ethylene oxide is then added in a controlled step to create hydrophilic end blocks. The length of each block is adjusted until the required 97:39 ratio is reached. The resulting waxy solid is purified, flaked or powdered, and shipped to cosmetic plants where it is melted straight into water-based formulations.
You will most often spot Poloxamer 238 in rinse-off and leave-on products that need gentle cleansing without stripping the skin. Common examples include facial cleansers, makeup removers, micellar waters, shower gels, baby wipes, shampoos and even some toothpaste and mouth rinses. It can also appear in lotions, serums and sheet masks where it keeps oily actives evenly distributed.
Poloxamer 238’s Cosmetic Benefits/Uses
This ingredient contributes two key actions that improve the performance and feel of many formulations:
- Cleansing: The molecule has both water-loving and oil-loving sections so it can surround dirt, excess sebum and makeup particles then lift them away when rinsed. Because the hydrophobic block is relatively small, the cleansing action is mild and well suited to sensitive skin
- Emulsifying: By positioning itself at the boundary between oil and water, Poloxamer 238 stabilizes emulsions and prevents separation. This allows brands to create silky lotions or clear gels without heavy surfactants or high levels of preservatives, improving texture and shelf life
Who Can Use Poloxamer 238
Because it is a mild non-ionic surfactant without common allergens, Poloxamer 238 is considered suitable for virtually every skin type including sensitive, dry, oily and combination skin. People with severely compromised or broken skin should still proceed cautiously, as any surfactant can sting on open cuts.
The ingredient is fully synthetic and contains no animal-derived components, making it appropriate for vegans and vegetarians. Most suppliers also certify it as cruelty free, though brand policies on animal testing can differ by region.
Current safety data show no systemic absorption at the low levels used in cosmetics, so products containing Poloxamer 238 are generally viewed as safe for those who are pregnant or breastfeeding. This is not medical advice and anyone expecting or nursing should run their routine past a healthcare professional to be on the safe side.
Poloxamer 238 does not increase sun sensitivity and has no known interactions with common UV filters or actives like retinol or vitamin C. Its gentle profile even makes it popular in baby wipes and eye makeup removers.
Potential Side Effects/Adverse Reactions
Reactions to topical Poloxamer 238 can vary from person to person. The following list covers potential side effects yet most users will not experience any issues when the ingredient is used at standard cosmetic levels.
- Mild transient redness or stinging especially if applied to broken or very dry skin
- Dryness or tightness when formulas contain high concentrations or are used too frequently without follow-up moisture
- Allergic contact dermatitis extremely rare but possible in individuals with specific sensitivities
- Eye irritation if a concentrated solution accidentally gets into the eyes before dilution or rinsing
- Enhanced penetration of other ingredients which could amplify irritation from harsher actives present in the same formula
If any discomfort, rash or persistent irritation occurs discontinue use immediately and consult a healthcare professional.
Comedogenic Rating
Rating: 0/5 Poloxamer 238 is highly water soluble, forms no greasy film and rinses away completely, leaving little chance for residue to block pores. It acts mainly at the surface to lift dirt rather than penetrating or sitting in follicles, which explains its classification as non-comedogenic.
Suitable for those prone to acne or breakouts
Because it can improve the rinse-off of heavier emollients, formulators sometimes use it to make otherwise rich products more acne friendly
Summary
Poloxamer 238 serves as a mild cleanser and emulsifier. Its block structure gives one end that loves oil and another that loves water so it can surround grime then help it wash away while also keeping oil-in-water mixtures smooth and stable.
Although not as famous as glycerin or hyaluronic acid, it has carved out steady popularity in micellar waters, gentle face washes and baby care thanks to its balanced cleansing power and soft skin feel.
The ingredient is regarded as very safe for topical use with a low risk of irritation or allergy. Still, skin can be unpredictable so it is wise to patch test any new product that contains Poloxamer 238 before fully integrating it into a routine.