What are the ingredients in NAC sourced from? Ceylon Keeslar October 12, 2021 23:23 Updated Follow Ingredient Source N-Acetyl-L-Cysteine Synthetic Related articles Are there any warnings or side effects when using NAC? What is the purpose of each ingredient in NAC? Why does Optimal Prenatal contain such a high amount of Vitamin A in the retinol form? What are the ingredients in Optimal CoQ10 derived from? Comments 0 comments Article is closed for comments.