Diethanolamine (DEA) is an alkaline organic compound used in cosmetics primarily as a pH-balancing agent and emulsifier, and to form surfactant derivatives that improve foaming and texture. It is a formulation aid rather than a therapeutic active.
| Reported effect | How often | Notes |
|---|---|---|
Skin irritation | Common | Can cause irritation, dryness, or stinging, especially at higher concentrations or with prolonged contact. |
Allergic contact dermatitis | Uncommon | Sensitization has been reported in some individuals on patch testing. |
Eye and mucous membrane irritation | Uncommon | Irritating to eyes upon contact in rinse-off and leave-on products. |
Nitrosamine formation concern | Rare | May react with nitrosating agents to form potentially carcinogenic nitrosamines; regulated/restricted in many regions. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.
Peer-reviewed papers on this ingredient, via PubMed.