I’ve been using products with niacinamide and tretinoin (all-trans retinoic acid) for several years now and I never wondered nor took the time to google if they should or should not be applied simultaneously, and if it’s ok to do that, how would I layer it? Which one should come first?
That is until yesterday, when Kate asked me this in the comments:
I use both acretin and olay natural white night cream, since we are supposed to apply both at night, which one do i apply first? Please advise.
And here’s my answer:
Hi Kate! I believe that the active ingredient of Olay Natural White is niacinamide (as with most of Olay’s whitening and anti-aging products) and the generic name for Acretin is tretinoin.
Though I might not be the best person to answer your question — I’m neither a scientist, chemist, nor a dermatologist — I put together 2 articles and a study, and quoted lines within those, that might help you/ us.
From Yahoo’s Health Section. “For maximum results, apply B3 (niacinamide) in the morning and evening. To reduce irritation from your retinoid (tretinoin is a retinoid), use it in conjunction with niacinamide. “Mix them together in the palm of your hand before applying—they won’t inactivate each other,” says Baumann. Besides decreasing side effects, the combo produces superior anti-aging benefits.”
From PubMed. “The most common adverse effects that are related to all-trans retinoic acid (atRA)* treatment are irritation and dryness of the skin. atRA therapy is reported to impair barrier function as achieved by trans-epidermal water loss (TEWL). Treatment with nicotinamide (niacinamide) prior to initiation of atRA therapy provides additional barrier protection and thus reduces susceptibility of retinoic acid.”
From Paula’s Choice. “For best results, any form of vitamin A/retinol (e.g. tretinoin) should be used with other anti-aging products containing rejuvenating ingredients such as antioxidants, skin-repairing ingredients, and different cell-communicating ingredients such as niacinamide. Despite retinol’s superstar status, treating signs of aging is far more complex than any one ingredient can address!”
From these articles, it seems best to either mix them together or put Olay Natural White first, wait a few minutes, then apply acretin/ tretinoin.
I hope this helps.
But I strongly suggest that you ask Colins Beauty Pages, Future Derm, and The Beauty Brains too. They entertain consumer questions and they are professionals. They could be more equipped to answer this question and any other ingredient-related questions you may have.