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Common Name
Undecylenoyl Phenylalanine
Undecylenoyl Phenylalanine
Amino Acids
Present in
Under analysis


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Biochemical Mechanism
Level of evidence
Under analysis

Regimen Lab Skincare Encyclopedia

Undecylenoyl Phenylalanine

*Preliminary Lab Notes* - Full Entry Under Development


Regimen's Take

The full Regimen Lab Skincare Encyclopedia Entry for Undecylenoyl Phenylalanine is in development. Check back in a few weeks for an update!

What is Undecylenoyl Phenylalanine?

Undecylenoyl Phenylalanine is a compound that includes amino acids and lipid residue, used in cosmetics and personal care products, specifically whitening formulas, to prevent skin cells from producing melanin pigmentation. Undecylenoyl Phenylalanine inhibits melanotropin, a melanin stimulator found in the skin. Melanotropin controls tyrosinase activity (tyrosinase being an essential enzyme in the production of melanin), melanin (eumalanin) synthesis and melanosome; therefore, by preventing the production of melanotropin, the pigmentation process is reduced or halted.

Clinical Studies:

A study was done to evaluate the efficacy and safety of a preparation containing undecylenoyl phenylalanine 2% in the topical treatment of solar lentigines. In total, 36 patients with solar lentigines of the hands were randomly assigned to apply the active preparation on one side and the vehicle alone on the other side, twice daily for 12 weeks. Undecylenoyl phenylalanine 2% is a novel depigmenting agent, which possibly acts as an alpha-melanocyte-stimulating hormone antagonist, thus inhibiting melaninogenesis. It achieved a significant lightening of the lesions with minimal side-effects. Most patients were satisfied with the improvement.

Clin Exp Dermatol. 2010 Jul;35(5):473-6. doi: 10.1111/j.1365-2230.2009.03605.x. Epub 2009 Oct 23.