Ingredient review
Poloxamer 338
INCI: Poloxamer 338
A gentle synthetic emulsifier that helps cleansers rinse cleanly without stripping the skin.
In plain English
Poloxamer 338 is a man-made ingredient that helps oil and water mix together in products like cleansers and shampoos. It's known for being very mild on the skin and rinsing off easily, leaving little to no residue. Think of it as a helper that makes your face wash feel smooth and effective without being harsh.
Review score
Safety, usefulness, and evidence
Potentially useful with some tradeoffs
The evidence base is useful, but some claims depend heavily on the formula.
Risk flags are low for most users, though the finished product can still irritate.
- Source
- synthetic
- Evidence
- moderate
- Irritation
- low
- Clogging risk
- low
Quick decision guide
Useful, but context matters
Poloxamer 338 is generally a lower-concern ingredient when the full formula suits your skin.
Plain-English read
Treat this as a practical screening step before you compare products that contain this ingredient.
- Step 1Start with the score, then check the irritation and clogging risk before judging Poloxamer 338.
- Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
- Step 3If a product stings, breaks you out, or worsens irritation, judge the finished formula and stop using it even if the ingredient scores well.
Score terms in plain English
Irritation risk
lowLess likely to sting, burn, or bother most users, though sensitive skin can still react.
Clogging risk
lowLess likely to feel heavy or contribute to clogged pores for most skin types.
Evidence level
moderateThere is useful support, but formula details and claim strength still matter.
What it is
Poloxamer 338 is a synthetic block copolymer made from ethylene oxide and propylene oxide. It belongs to the poloxamer family, which are non-ionic surfactants widely used in cosmetics and personal care for their gentle cleansing and emulsifying properties.
How it works
In a cosmetic product, Poloxamer 338 reduces the surface tension between oil and water, allowing them to blend into a stable mixture. It also helps suspend dirt and oil so they can be rinsed away easily. Because it is non-ionic, it is less likely to irritate the skin compared to some other surfactants.
Pros
Very mild on skin
Poloxamer 338 is one of the gentlest surfactants, making it suitable for daily use even on sensitive skin.
Rinses cleanly
Unlike some cleansers that leave a residue, Poloxamer 338 washes off completely, reducing the chance of clogged pores.
Cons and cautions
Synthetic ingredient
It is not naturally derived, which may be a drawback for those committed to natural or organic skincare routines.
Can be drying at high levels
In very high concentrations, it may still strip some moisture from the skin, though this is uncommon in well-formulated products.
Best for
- People with normal to combination skin looking for a mild cleanser
- Those who prefer rinse-off products that don't leave a film
Use caution if
- Individuals seeking 100% natural or plant-based ingredient lists
- Those with known sensitivity to synthetic surfactants (rare)
Usage tips
Safety summary
Poloxamer 338 has a strong safety profile with low irritation and sensitization potential. It is widely used in personal care and medical products. No significant safety concerns have been raised by regulatory bodies.
Research notes
Studies confirm that Poloxamer 338 is a mild surfactant with low cytotoxicity. It is well-tolerated in ophthalmic and topical applications. Research is ongoing regarding its environmental persistence.
Common label clues
- Typical concentration
- 1% to 10% depending on product type
- Regulatory status
- Approved for use in cosmetics by the FDA and EU CosIng database. Generally recognized as safe at typical concentrations.
- Common uses
- Cleansers, Shampoos, Body washes, Makeup removers
- Environmental note
- Poloxamers are synthetic and not readily biodegradable, though they are considered low in aquatic toxicity at typical use levels.
Good to know
- Poloxamer 338 is also used in contact lens solutions due to its gentle nature.
- It is often listed as Pluronic F108 on ingredient labels.
Common questions
What is Poloxamer 338 in beauty products?
Poloxamer 338 is a man-made ingredient that helps oil and water mix together in products like cleansers and shampoos. It's known for being very mild on the skin and rinsing off easily, leaving little to no residue. Think of it as a helper that makes your face wash feel smooth and effective without being harsh.
What does Poloxamer 338 do in a beauty product?
In a cosmetic product, Poloxamer 338 reduces the surface tension between oil and water, allowing them to blend into a stable mixture. It also helps suspend dirt and oil so they can be rinsed away easily. Because it is non-ionic, it is less likely to irritate the skin compared to some other surfactants.
Is Poloxamer 338 safe for most people?
Poloxamer 338 has a strong safety profile with low irritation and sensitization potential. It is widely used in personal care and medical products. No significant safety concerns have been raised by regulatory bodies.
Who should be careful with Poloxamer 338?
Individuals seeking 100% natural or plant-based ingredient lists Those with known sensitivity to synthetic surfactants (rare)
Research sources
Ingredient reviews are educational and are not medical advice. Patch test new products and ask a licensed clinician about persistent irritation, allergies, pregnancy-specific questions, or diagnosed skin conditions.