An amino acid that strengthens and moisturizes hair and skin, helping to improve texture and resilience for a smoother, healthier appearance.
Formula
C6H15ClN2O2
Mol. Weight
182.65
CAS #
657-27-2, 10098-89-2, 22834-80-6
Form
Powder
Plant-Derived
Synthetic. Lysine HCl is synthesized from L-lysine, a naturally occurring amino acid produced through bacterial fermentation. The free base lysine is then converted to its hydrochloride salt form through acid treatment.
Function
Hair Conditioning | Skin Conditioning
Benefits
Locks in moisture
Traditional Use
L-lysine was identified as an essential amino acid in the early 20th century. Its use in skincare is a modern application developed to support collagen formation and skin barrier function.
Skin Types
all-skin-types
Best For
Target
General
Melanin-Rich Skin
Suitable
Pregnancy Safe
Yes
EWG Score4
CIR Safety Findings
medical-approval, all-shades-safe, Not Phototoxic
Concentration Guide
Industry Max
Industry typically uses up to 0.7% in leave-on products (28 products reported). Source: CIR Safety Assessment (CIR Seq 607).