Ingredient review

Acrylamidomethylpropane Sulfonic Acid

INCI: 2-ACRYLAMIDO-2-METHYLPROPANE SULFONIC ACID

A synthetic thickener and stabilizer that helps create lightweight, non-greasy gel textures in skincare and haircare.

beautyskincarethickener

In plain English

This is a synthetic ingredient that helps make skincare products feel smooth and lightweight. It acts like a sponge, absorbing water and turning into a gel, which gives products a nice texture without feeling sticky or heavy. You'll often find it in clear gels, serums, and sunscreens to keep the formula stable and easy to spread.

Quick decision guide

Useful, but context matters

Acrylamidomethylpropane Sulfonic Acid 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.

  1. Step 1Start with the score, then check the irritation and clogging risk before judging Acrylamidomethylpropane Sulfonic Acid.
  2. Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
  3. 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

low

Less likely to sting, burn, or bother most users, though sensitive skin can still react.

Clogging risk

low

Less likely to feel heavy or contribute to clogged pores for most skin types.

Evidence level

moderate

There is useful support, but formula details and claim strength still matter.

What it is

A synthetic polymer derived from acrylic acid, designed to thicken water-based formulas and improve their stability and feel on the skin.

How it works

When mixed with water, the polymer chains swell and form a network that traps water, creating a gel-like consistency. This helps suspend other ingredients, prevents separation, and gives a smooth, non-tacky feel when applied to the skin.

Pros

Lightweight texture

Creates a silky, non-greasy feel that absorbs quickly, ideal for gel creams and serums.

Stabilizes formulas

Helps keep ingredients evenly mixed and prevents separation, extending product shelf life.

Cons and cautions

Synthetic origin

Not natural or biodegradable, which may be a concern for eco-conscious consumers.

Potential tackiness at high levels

If used in very high concentrations, it can leave a slightly sticky or film-like residue on skin.

Best for

  • Anyone who prefers lightweight, gel-based moisturizers or serums
  • People with oily or combination skin looking for non-greasy hydration

Use caution if

  • Those seeking 100% natural or organic skincare formulations

Usage tips

Use in gel-based products like serums or lightweight moisturizers for best texture results.
Pair with humectants like glycerin to boost hydration without adding grease.

Safety summary

Considered safe for topical use in cosmetics at typical concentrations. Low irritation and comedogenic risk. No significant safety concerns reported in regulatory reviews.

Research notes

Limited independent clinical studies on this specific ingredient, but it is widely used and accepted as a safe cosmetic thickener. Safety assessments by industry panels support its use.

Common label clues

Typical concentration
0.1% to 2%
Regulatory status
Approved for use in cosmetics in the EU, US, and other major markets. Generally recognized as safe at typical use levels.
Common uses
Gels, Serums, Moisturizers, Sunscreens, Hair styling products
Environmental note
Synthetic polymer; not readily biodegradable. Some manufacturers are exploring bio-based alternatives.

Good to know

  • Often listed as 'AMPS' on ingredient labels.
  • Commonly used in combination with other thickeners like carbomer for enhanced stability.

Common questions

What is Acrylamidomethylpropane Sulfonic Acid in beauty products?

This is a synthetic ingredient that helps make skincare products feel smooth and lightweight. It acts like a sponge, absorbing water and turning into a gel, which gives products a nice texture without feeling sticky or heavy. You'll often find it in clear gels, serums, and sunscreens to keep the formula stable and easy to spread.

What does Acrylamidomethylpropane Sulfonic Acid do in a beauty product?

When mixed with water, the polymer chains swell and form a network that traps water, creating a gel-like consistency. This helps suspend other ingredients, prevents separation, and gives a smooth, non-tacky feel when applied to the skin.

Is Acrylamidomethylpropane Sulfonic Acid safe for most people?

Considered safe for topical use in cosmetics at typical concentrations. Low irritation and comedogenic risk. No significant safety concerns reported in regulatory reviews.

Who should be careful with Acrylamidomethylpropane Sulfonic Acid?

Those seeking 100% natural or organic skincare formulations

Research sources

Cosmetic Ingredient Review (CIR) - Safety AssessmentOpenPubChem - Compound SummaryOpenEuropean Chemicals Agency (ECHA) - InformationOpen

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.