0.3% retinol, mid-range as over-the-counter retinol concentrations go — high enough to be a real dose, not so high that most users need to start below the lowest step on the bottle. Retinol converts in stages to retinoic acid inside the skin; how quickly that conversion happens, and how a given user tolerates it, varies enough between people that we describe this as a starting point, not a guarantee.
Ceramide NP is included specifically because retinoids are well known to disrupt barrier function in the first weeks of use for some people — this is a formulation choice made to offset a known real side effect, not a marketing pairing.
