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Some things are just meant to be together. We could list a few, but let your imagination run wild. Other things are better suited on their own, especially when it comes to certain skin care products. Powerful ingredients like retinol, vitamin C, benzoyl peroxide, and even some acids demand to be the star of the show. Sharing the scene could lead to major drama in the form of irritation, redness, temporary staining, or just a general lack of desired results. “There are so many great active ingredients out there and it might seem like using more would give you better results, but that isn’t always the case,” says Aegean Chan, a certified dermatologist based in Santa Barbara, Calif.
Not sure if you’re giving your favorite serums and creams the attention they need? Well, we asked Chan and many other board certified dermatologists to share which skin care ingredients you should do not mix – never, as well as the alternatives they recommend.
1. Retinol and vitamin C
These effective ingredients may brighten your complexion and fade dark spots better than anything else, but in tandem, they won’t double your glow. If anything, your face will be extremely uncomfortable. Both actives have the potential to irritate your skin, Chan says.
Minimize redness and flaking by separating your favorite retinol and vitamin C serums. Incorporate vitamin C into your morning routine, especially since it works best during the day, she adds. (We have a handy list of our favorite serums fortified with this product if you are looking for a new product.) Retinol is best for your pm skin care line, “because light can increase degradation. of the product, ”says Chan.
As an alternative, kojic acid is your best bet for pairing with retinol and vitamin C for optimal lightening benefits, says certified dermatologist Azadeh Shirazi, based in La Jolla, Calif. The sake by-product works wonders with day and night routines to decrease the appearance of hyperpigmentation, especially with the serum below.
2. Vitamin C and alpha hydroxy acids (AHAs)
In the overlay episode of The Science of Beauty podcast, Marie Jhin, a certified dermatologist based in Silicon Valley, Calif., Warned of the duo as they could cause irritation. Consider the same tips as above: vitamin C in the morning; AHA at night.
3. Vitamin C and benzoyl peroxide
If you’ve used these ingredients side by side, you may have noticed that your skin hasn’t been as shiny as you hoped. Well, there is an explanation for that: Benzoyl peroxide negates the magical benefits of vitamin C by breaking it down or oxidizing it.
4. Retinol and benzoyl peroxide
While these two powerful ingredients are effective acne ingredients, you should never combine them. Reason: Benzoyl peroxide can oxidize and break down tretinoin, Chan notes. “The two ingredients neutralize each other, making each less effective and can increase the risk of irritation when stacked,” adds Caroline Robinson, a Chicago-based dermatologist.
Instead, Robinson and Chan recommend relegating benzoyl peroxide to your morning routine and retinol to your nighttime routine. Neutrogena’s Stubborn Acne + Marks range makes this easy to remember.
Benzoyl peroxide (or BPO, as Robinson calls it) pairs well with a prescription-grade ingredient called topical clindamycin, which “works synergistically with BPO to fight acne-causing bacteria,” says Robinson. . Retinol, on the other hand, works best with hydrating formulas based on glycerin, hyaluronic acid and niacinamide, she adds.
5. Retinol and AHA
Another recipe for major irritation is retinol mixed with alpha hydroxy acids, like glycolic, lactic, and citric. “Both of these ingredients disrupt the skin barrier,” Chan explains. If you double your skin tone with them, excessive dryness, redness, tenderness or rash are very possible results.
Instead, alternate the days you cast them. Once or twice a week, Chan achieves an AHA with a concentration of 10-20%. The other days – and if his skin does not act – the retinol is put into action.
6. Retinol and salicylic acid
Another marriage of acid and retinol that should be avoided includes that of the beta-hydroxy acid (BHA) variety. Salicylic acid, in particular, is far too drying and irritating for your skin to resist, says Shirazi.
Shirazi also suggests that niacinamide replaces both salicylic acid and retinol, as it has anti-inflammatory properties to help calm the skin. Along with salicylic acid, niacinamide effectively banishes rashes by regulating sebum production, shrinking clogged pores, and exfoliating the skin, she says.
Collagen peptides, which increase the elasticity and firmness of the skin, are another good option in place of salicylic acid, as retinol improves their penetration. “The combination of these ingredients does not lead to irritation or excessive exfoliation, which keeps the skin barrier healthy,” says Shirazi.
7. Dapsone aka Aczone & Benzoyl Peroxide
You know how they say if you eat too many carrots you will start to look like them? Well, smoothing out topical dapsone and benzoyl peroxide at the same time can cause the same type of orange discoloration on your skin without consuming a single carrot, according to Chan. Stick to just one of the acne treatment ingredients at a time to maintain your true colors. Also, keep in mind that salicylic acid and benzoyl peroxide are still a viable pairing.
8. Benzoyl peroxide and hydroquinone
One of the crucial tips dermatologists share with their patients prescribing hydroquinone is to avoid fusing it with benzoyl peroxide in your skin care routine. Together, they can do the exact opposite of what you want them to do and end up temporarily staining your skin.
9. Hydroquinone and AHA
Like retinol, hydroquinone and AHAs can cause irritation on their own, Chan says. You can also avoid the problem as much as you can by separating them from your morning and nighttime routines or looking for a hydroquinone substitute, like tranexamic acid, licorice extract, or vitamin C. We love the serum. Eadem Milk Marvel anti-stain. as an alternative.
Overall, Chan advocates using any potentially irritating ingredient alone for at least a few weeks. “If a certain ingredient causes skin irritation on its own, you absolutely should not use it with other potentially irritating ingredients,” she explains. “Even a ubiquitous ingredient like niacinamide can potentially irritate the skin.”
Also, giving your skin a break from the actives is extremely important, adds Chan. If you notice any irritation or dryness, be sure to seek advice from a certified dermatologist and in the meantime try a gentle cleanser and heavy moisturizer.
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