What Skincare Products Shouldn't I Mix?

We can’t understate the importance of correctly mixing the ingredients in your skincare routine. Not only will this prevent irritation, but it can make your products more effective and even keep them from going to waste. 

To give your skincare routine the most bang for your buck, this guide from Nourishing Biologicals created this crash course on skincare mixology 101. In it, we go over the top ingredients that you’re likely to find in your products and discuss what they should never be mixed with. 

Read on everything you should know about which skin care products not to mix. 

1. Vitamin C

Vitamin C is a powerful antioxidant that, if applied in the morning, may help protect the skin from sun damage. It has also been shown to reduce the appearance of hyperpigmentation and dark spots. Needless to say, it’s an excellent ingredient for a bright complexion. 

You can (and should) mix vitamin C with your SPF. That’s because while your sunscreen or sunblock does protect your skin from the sun’s damaging UV rays, it may not be enough on its own. Adding vitamin C to the mix can give your skin some extra security — while adding a host of other benefits.

You can also mix vitamin C with other antioxidants, like vitamin E. Using two antioxidant products at once can boost the results you get. And because antioxidants aren’t known to be harsh, mixing different ones shouldn’t irritate your skin.

The only exception here is retinol. Because it’s a vitamin A derivative, it’s technically considered an antioxidant. However, retinol supports skin cell turnover, which actually makes your skin more sensitive to the sun’s rays. 

Retinol is definitely not something you want to wear in the morning — unlike vitamin C. And since vitamin C isn’t the most effective at night, we can’t think of any reasons why you should mix retinol and vitamin C. 

2. Niacinamide 

Also known as vitamin B3, niacinamide is another antioxidant we’re particularly fond of. It’s known for its soothing effects, which can help ease irritation, even out the look of discoloration, and brighten skin. 

Because niacinamide is soothing for skin, the side effects are minimal. It’s not known to cause irritation, so you should safely be able to mix it with other skincare products in your routine.

3. Hyaluronic Acid 

Hyaluronic acid is one of the world’s best humectants, which is essentially a molecule that helps to attract water. Applying it to your skin can give you a plump, dewy, and soft appearance.

Hyaluronic acid is naturally found in the body, so it’s not known to be irritating. You can mix it with any other skincare ingredients. For best results, we recommend pairing it with a hydrating essence.

You can find ample amounts of hyaluronic acid in our Miracular Serum — in addition to a host of other nourishing botanical ingredients. 

4. AHAs and BHAs

Alpha-hydroxy acids and beta-hydroxy acids are active ingredients that are excellent for exfoliation. And no, not the type made out of harsh salts or beads. Instead, these chemical exfoliators penetrate the skin to support cell turnover.

Some well-known ingredients in this group include salicylic, glycolic, and lactic acid. But while these are excellent for their intended purpose, they can make your skin slightly irritated. That’s why we recommend pairing them with our hydrating Miracular Skin Essence and plenty of SPF to protect your skin from the sun. 

Some ingredients you want to be on the lookout for include ceramides, glycerin, and hyaluronic acid. These are proven to aid in skin hydration while soothing irritation.

What you don’t want to mix your AHAs and BHAs with is another exfoliating ingredient — which applies to all our retinol lovers. The vitamin A derivative is known to be harsh, so adding it to the mix can increase sensitivity. 

It’s also important to avoid mixing different acids. If you’re using glycolic acid, that should be all you use, and the same rule applies to salicylic acid and lactic acid. 

Last, be wary of scrubs, as these can be even harsher than chemical exfoliants. If you must use one, avoid using AHAs or BHAs the night before. 

5. Retinol 

This vitamin A derivative is the golden standard in anti-aging skincare due to its clinically proven ability to promote collagen formation. Retinol is an excellent way to even out the look of discoloration, minimize the appearance of fine lines and wrinkles, and even battle breakouts. 

So, what’s the catch? First and foremost, retinol can be extremely irritating, especially if you start with a high dose. And regardless of which strength you use, retinol can make the skin extremely susceptible to sun damage. 

To offset retinol's negative effects, pair it with a moisturizing ingredient like hyaluronic acid. And to protect your skin from the sun, never apply retinol in the morning before going out. Always use it at night and wash it off when you wake up. Follow it up with a broad spectrum sunscreen or sunblock to shield your skin from the sun’s rays. 

What should you never mix retinol with? Anything irritating. That includes salicylic, glycolic, and lactic acids and common blemish-fighting ingredients like benzoyl peroxide. 

6. Benzoyl Peroxide 

If you have frequent acne breakouts, benzoyl peroxide can be a game changer. It’s a super potent ingredient that’s known for killing acne-causing bacteria. Unfortunately, it tends to be very drying. 

This is exactly why we recommend combining benzoyl peroxide with other moisturizing ingredients. Try using a gentle cleanser, like our Miracular Cleanser, to lift off the dirt without stripping your skin of moisture. And always follow up with an ultra-hydrating face cream. 

Depending on how your skin reacts to benzoyl peroxide, you might need to wear moisturizer under this ingredient. Doing so can buffer some of the drying effects of benzoyl peroxide.

One ingredient you should never use with benzoyl peroxide is retinol. When mixed together, benzoyl peroxide and retinol can deactivate one another. This effect seems to be reduced if the products are applied to the skin one after the other — instead of mixing them right away. 

And, of course, combining retinol with benzoyl peroxide can be very irritating. So, if you already have sensitive skin, try to avoid this combination completely. 

7. Clindamycin 

Clindamycin is a topical antibiotic that’s used to treat acne. Applying it to the skin may restore the skin’s ratio of good to bad bacteria, reducing breakouts. 

Clindamycin is a fairly mild ingredient not known to cause significant irritation. It’s most effective when combined with other acne-fighting ingredients, like niacinamide, retinol, or benzoyl peroxide. You can safely mix clindamycin with other ingredients without reducing their effectiveness. 

Clindamycin doesn’t exactly discriminate between the different types of bacteria on your face. While some are indeed harmful and acne-causing, others are actually beneficial. So, it’s not the best idea to kill everything indiscriminately.

That’s why we recommend applying a topical probiotic to your skin when using clindamycin. Doing this can help restore some good bacteria while keeping the bad bacteria in check. 

8. Sunscreen or Sunblock 

Protecting your skin from the sun is one of the most important things you can do to prevent wrinkles, fine lines, hyperpigmentation, and other premature signs of aging. It’s especially important to use SPF if any of the above ingredients are in your skincare routine. 

There aren’t any skincare products that you shouldn’t mix with your SPF. On the contrary, if you’re using active skincare ingredients, then sunscreen is a must. Aside from going outdoors, you may consider applying it in front of your computer or television — as screens are thought to give off skin-damaging blue light. 

One thing you want to avoid is diluting your SPF with a serum or moisturizer. We get the appeal of simplifying your skincare routine, but adding another ingredient to your sunscreen or sunblock can reduce its potency and efficacy. 

However, you can layer your SPF with other skincare products. Just make sure that everything goes on before your sun protection and has a few minutes to absorb. 

Skincare Mixology With Nourishing Biologicals 

There are plenty of ingredients that make their way into our skincare routines. Whether it’s retinol, hyaluronic acid, or niacinamide, these active ingredients are incredibly effective for improving common skincare concerns. 

However, just because some skincare ingredients work well doesn’t mean they work well together. As a rule of thumb, it’s good to avoid mixing skincare products that are known to cause irritation. And when using such products, it’s essential to follow up with a nourishing moisturizer and protective SPF. 

At Nourishing Biologicals, our skincare products are made with nourishing botanical ingredients. So you can safely mix them with other products — for your best skin yet. 

Sources: 

Vitamin C in dermatology | PMC

Retinoids in the treatment of skin aging: an overview of clinical efficacy and safety | PMC

Benzoyl Peroxide | NCBI Bookshelf

Topical Probiotics: More Than a Skin Deep | PMC