A skin-identical lipid from the ceramide family, antimicrobial and calming in lab tests. Usually a supporting ingredient in barrier creams.
Phytosphingosine is a sphingoid base — one of the building blocks of ceramides, the lipids that seal the skin barrier — and occurs naturally in the skin's outer layer. It is added to barrier-repair moisturizers, often alongside ceramides and cholesterol, and to acne and scalp products.
In lab studies it inhibits acne bacteria and inflammation. Whether it adds much beyond the ceramides and occlusives it's formulated with is uncertain.
The main clinical data come from a small study co-authored by the ingredient's manufacturer, reporting antimicrobial and anti-inflammatory effects and improvement in acne-prone skin. Independent controlled trials are lacking.
Lab and small human studies, co-authored by the ingredient's manufacturer, found phytosphingosine antimicrobial against acne bacteria and anti-inflammatory, with improvements in acne-prone skin.