It’s best to avoid layering it with any chemical exfoliants like alpha or beta hydroxy acids. “These can change the pH and may effects the efficacy of ferulic acid,” points out Dr. Garshick.Posted by Unfamiliar on 14th Sep 2016 I bought the Ascorbic Acid to ensure my girlfriend and I could make Bathtub Bombs for Xmas presents...and in additio… Read More