Here at MDC, we're big fans of mixing and matching. From eye shadow and lipstick combos to nail and denim pairings, we love it all! However, there are certain beauty ingredients and products that do not come together in perfect harmony. This is especially true in the skincare world. With so many quick-fixing products and miracle ingredients at our fingertips, we are constantly adding new items to our skincare routine without giving it a second thought. Well, you should. While separately these skincare treatments are pure magic, when combined they are not exactly a match made in heaven. We did a little digging and heard from NY-based dermatologist Dr. Gervaise Gerstner on some not-so-dynamic duos to avoid.


Retinol and Acne Treatments
Retinol and popular acne ingredients such as benzoyl peroxide or salicylic acid are all mighty warriors in the battle against acne. However, mixing or layering them in your skincare routine can be a case of too many cooks in the kitchen. When brought together, they actually counteract each other and cause more damage than good: We're talking peeling, scarring and blistering (ew!). In fact, Dr. Gerstner suggests sticking to just one acne-fighting ingredient. "I wouldn't overload on acne products when first starting an acne regimen," she says. "Select either salicylic acid or benzoyl peroxide for starters." As a general rule, she adds, always get the opinion of your dermatologist when it comes to targeted treatments and solutions.

Vitamin C and Alpha Hydroxy Acids (AHA)
Both ingredients pack a wallop on their own and are commonly used to brighten the complexion and minimize age and sun spots. However, joining the two forces can be catastrophic. Applying too many acids to your face can lead to irritation, peeling and redness, especially when the ingredients are absorbed in concentrated amounts.

Retinol and Alpha Hydroxy Acids
Sensitive-skinned ladies, beware! Combining these two exfoliating, anti-wrinkle ingredients can send your poor complexion over the edge. Over-exfoliating the skin can lead to irritation, inflammation and breakouts. To avoid all these things, try alternating between the two in your skincare routine, switching them up every few months or so. Also, as a general rule, retinol should be applied at night, as it can make skin ultra-sensitive to UV rays.

Vitamin C and Benzoyl Peroxide
Science lesson: Benzoyl peroxide is an oxidizing agent, a property, which allows it to kill acne-causing bacteria. However, when it comes in contact with an ingredient like vitamin C that is oxidize-friendly, the two cancel each other out and lose their potency and effectiveness.

Salicylic Acid and Glycolic Acid
Similar to the retinol/AHA effect, combining these two potent ingredients can cause your skin to react in a rash-like manner. We're talking the redness, excessive dryness, irritation, etc. Just don't do it!

Which of these combative couples was most surprising? Tell us in the comments below!

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