Ingredient Concerns (Clogging/Allergy) and Xanthan Gum Use in Serum

Question

I would like to inquire about certain ingredients and their potential to clog pores or cause acne/allergic reactions. Specifically:

Do Polymethylsilsesquioxane, Boron Nitride, and Nylon-12 clog pores or cause allergic reactions?
Do Sericite (methicone coated) and Cyclomethicone clog pores or cause allergic reactions?

Additionally, I want to use Xanthan Gum as a thickener in a serum formulation. Can I add it to the water phase by mixing it with other ingredients before blending, or should I add it as the first or last ingredient? Which method is correct?

MySkinRecipes Expert · Accepted Answer

Regarding the ingredients and whether they clog pores or cause acne:

Polymethylsilsesquioxane, Boron Nitride, and Nylon-12: These ingredients generally do not clog pores and have a very low chance of causing allergic reactions.
Sericite (methicone coated) and Cyclomethicone: Sericite itself does not clog pores. Methicone and Cyclomethicone are silicones. While silicones themselves do not typically clog pores, they can potentially cause allergic reactions in some individuals, and clogged pores might be one symptom of such a reaction, possibly along with other symptoms or as the sole symptom.

Regarding using Xanthan Gum as a thickener in a serum:

You can add Xanthan Gum to the water phase using either method: mixing it with other ingredients in the water phase before blending, or adding it as the first or last ingredient. You can choose the method that is most convenient for your process.