What it is
Sodium Guaiazulene Sulfonate is a water-soluble form of guaiazulene, an azulene compound originally associated with chamomile and other botanical sources, modified by sulfonation to dissolve in water-based formulas. In cosmetics it is used as a soothing skin-conditioning ingredient and also imparts a characteristic blue tint. It is common in calming and post-sun style formulations where a gentle, comforting feel is the goal.
Safety & warnings
Water-soluble azulene derivatives are generally well tolerated and are valued specifically for their soothing, low-irritation profile. Because the material is intensely blue, it is used at very low concentrations. Sensitive individuals may rarely react to any botanical-derived constituent, so a patch test is reasonable for very reactive skin.
Origin & sourcing
Semi-synthetic. It is prepared by sulfonating guaiazulene, an azulene historically derived from plant sources such as chamomile, to produce a water-soluble sodium salt.
Questions everyone asks
Why is this ingredient blue?
It is a derivative of guaiazulene, an azulene compound that has an intense blue color, so even small amounts tint a formula blue.
What does it do for the skin?
It is used as a soothing skin-conditioning agent in calming and comforting formulations.