Sometimes, but there are a couple of factors to consider before diving in, like the strength of the actives, how sensitive your skin is, and whether the vitamin C serum has an acidic or balanced composition
Discard at that date, or sooner if the solution turns cloudy, discolors beyond its normal pink-to-red, or shows particulates
Use small bowls
Straka E, Ellinger I, Balthasar C, Scheinast M, Schatz J, Szattler T, Bleichert S, Saleh L, Knfler M, Zeisler H, Hengstschlger M, Rosner M, Salzer H, Gundacker C (2015) Mercury toxicokinetics of the healthy human term placenta involve amino acid transporters and ABC transporters
Human data are extremely limited and consist only of a small number of low-quality or small-sample studies
The two protocols address different systems and can run concurrently