Home › Ingredients › Stearamidopropyl Dimethylamine
Stearamidopropyl Dimethylamine in skincare
pH-activated conditioning amine; lighter conditioning feel with minimal buildup; common in fine hair conditioners.
Found in both rinse-off and leave-in hair care products. AM and PM appropriate. Formulated at acidic pH (4–5) where it becomes protonated and cationic. Effective conditioning under correct pH conditions. Considered one of the 'lighter' conditioning agents less prone to buildup compared to quaternary ammonium salts.
What it is
Stearamidopropyl Dimethylamine (SAPDMA) is a tertiary amine derived from stearic acid (C18) that becomes protonated (positively charged) at acidic pH (4.5–5.5), enabling it to electrostatically bind to negatively charged hair cuticles. The same cationic conditioning mechanism as quaternary ammonium compounds, but pH-dependent. Its conditioning effect is effective but lighter and less persistent than behentrimonium chloride, making it well-suited for fine or limp hair that easily loses volume. Less buildup potential and rinses cleanly. The tertiary amine functionality also contributes mild emulsification properties. CIR Expert Panel reviewed as safe in cosmetic products. Typical use: 1–3% in conditioners and hair treatments. Also used as a pre-neutralized emulsifier when combined with an acid.
The facts
| Category | Cationic Conditioning Agent (Tertiary Amine) |
| Typical use | Morning and evening |
| Concentration YARAI treats as a full dose | 3% |
Why the amount matters, not just the presence
Most ingredient checkers tell you whether something is in the bottle. That is a smaller question than it sounds. Stearamidopropyl Dimethylamine at 3% and stearamidopropyl dimethylamine at a trace level are not the same ingredient in any way that affects your skin.
An ingredient list is ordered by quantity, so position carries real information. YARAI reads that position and scores accordingly, which is why the same ingredient can land differently in two different products.
The honest limit: a list gives order, not percentages. Estimating concentration from position is an estimate. It is a better estimate than ignoring position, and it is still an estimate. We would rather tell you that than let a number look more certain than it is.
Common questions
What does stearamidopropyl dimethylamine do in a skincare product?
pH-activated conditioning amine; lighter conditioning feel with minimal buildup; common in fine hair conditioners.
How much stearamidopropyl dimethylamine should a product contain?
YARAI treats 3% as a full dose for this ingredient. Below that, the ingredient is present but is scored as contributing less. An ingredient list gives you the order of ingredients, not their percentages, so this is an estimate read from position rather than a measurement.
When should I use stearamidopropyl dimethylamine?
Found in both rinse-off and leave-in hair care products. AM and PM appropriate. Formulated at acidic pH (4–5) where it becomes protonated and cationic. Effective conditioning under correct pH conditions. Considered one of the 'lighter' conditioning agents less prone to buildup compared to quaternary ammonium salts.
Check your own products
Point your camera at a product. YARAI identifies it from the label, finds that product's full ingredient list from published sources, and scores it. No barcode and no box needed, which is how it handles imported and small-brand products.
Concern level, category and thresholds on this page are read directly from the same data the YARAI app scores with, so this page and the app cannot disagree. EU figures cite Regulation (EC) No 1223/2009. Last built 2026-09-09. Nothing here is medical advice.