Tromethamine
pH regulator and buffer. Maintains stable formula pH – especially with carbomers and acids – without skin activity.
Supporting ingredient
It gives a product its texture, stability or shelf life. It has no claimed effect on the skin, so an efficacy tier does not apply. What is known about its safety is below
Tolerability and safety
- Irritation potential
- Low
- Allergen risk
- Low
- Pregnancy
- Safe
- Suitable for
- Normal, Dry, Oily, Combination, Sensitive
About this ingredient
Tromethamine (TRIS, tromethamol) is an amino alcohol that serves as a pH buffer and regulator. It is the alternative to triethanolamine (TEA) following tighter nitrosamine regulation in the 2010s. In medicine it is used as an acidosis corrector. Mechanism. A weak base – neutralises acidic polymers (carbomers, acrylates) into a stable gel. Also buffers formula pH in the 7-9 range, important for preservative and active stability. Where applied. Face washes, carbomer-based creams, sunscreens with octocrylene and avobenzone, pharmaceutical emulsions. In Spain – in La Roche-Posay Anthelios, Bioderma Photoderm, Caudalie Vinosun lines, gradually replacing TEA in formulations. Evidence base. Functional ingredient with no skin RCTs. CIR confirmed safety in 2008. Safety. Non-sensitising, non-comedogenic. Unlike TEA, it does not form nitrosamines on contact with nitrites, which makes tromethamine the preferred choice in current formulations. Pregnancy and lactation – safe. Topical systemic absorption is minimal.
Frequently asked questions
Is Tromethamine safe during pregnancy?
Tromethamine is considered safe during pregnancy at typical cosmetic concentrations. Systemic absorption through the skin is minimal.
What skin types is Tromethamine for?
Tromethamine suits: normal, dry, oily, combination, sensitive.
What is Tromethamine and what does it do in cosmetics?
pH regulator and buffer.
What's the INCI name for Tromethamine?
The INCI name is Tromethamine. It may also appear as: TRIS.
See Tromethamine in a product composition right on the store page
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Similar role in the formula
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