Polyquaternium-39 is a synthetic cationic copolymer used in skincare and haircare as a film-forming, conditioning, and antistatic agent that improves texture and substantivity. It is considered a formulation/base ingredient rather than a therapeutic active.
| Reported effect | How often | Notes |
|---|---|---|
| Skin irritation | Rare | Mild transient redness or stinging reported infrequently, typically in sensitive individuals. |
| Allergic contact dermatitis | Very rare | Isolated sensitization reports; uncommon for this polymer class. |
| Eye irritation | Rare | Possible mild irritation if formulations contact the eyes. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.