By Skincare Junkie Inc

5 Active Skincare Ingredient Interactions You Need to Know About

The field of dermatology is constantly evolving. Skincare brands are releasing formulations filled with new and more potent ingredients. Does your beauty cabinet resemble a chemistry lab? Do you know what ingredients work well together and which don’t? Do you know how to layer your active ingredients correctly? Read to learn more. 

What Are Active Ingredients?

Active ingredients are components known for their targeted action on the skin. Common examples include: 

  • Retinol, a derivative of vitamin A, known for its anti-aging and skin-renewing properties. Retinoids work by stimulating production of collagen, improving skin tone and pigmentation, reducing fine lines, and helping prevent acne. 
  • Niacinamide, known as vitamin B3, has multiple benefits. It protects skin from environmental pollutants, reduces excess sebum production (so helps prevent acne), improves the skin's barrier function, evens out skin tone, and reduces inflammation. 
  • AHAs, Alpha Hydroxy Acids (e.g., glycolic and lactic acid), are water-soluble acids that exfoliate and promote a brighter, more even complexion. BHAs, Beta Hydroxy Acids (e.g., salicylic acid), are oil-soluble acids that penetrate deep to unclog pores and target acne. 
  • Vitamin C, also known as ascorbic acid, is a powerful antioxidant. It helps protect the skin against UV and environmental pollutants, and prevent pigmentation and inflammation.

5 Most Common Active Ingredient Interactions

As the number of available potent skincare ingredients and products grows, it becomes easier to mix incompatible active ingredients or overuse them. Mixing actives can lead to them canceling each other out, or—worse—skin irritation, redness, and peeling. 

1. Retinol and AHAs or BHAs 

Retinol increases skin cell turnover and hydroxy acids exfoliate the skin. When used together, they can lead to over-exfoliation and cause irritation, redness, and peeling. For example, using a retinol product and a cleanser with salicylic acid at the same time can lead to increased sensitivity and inflammation. 

Dermatologists advise using these active ingredients on alternate days for most users. Make sure you apply sunscreen during the day, as both increase sensitivity to the sun. 

2. Retinol and Vitamin C 

Retinol works well with hyaluronic acid (layer it on top of retinol), niacinamide (sandwich retinol in between), and peptides. However, combining retinol and vitamin C in a skincare routine can be tricky, as they both have low pH levels and can irritate the skin when used together. 

Sunlight actually breaks retinol down and its use increases sensitivity to the sun, which is why dermatologists advise to apply vitamin C in the morning to protect from UV-induced oxidation and free radical damage and use retinol at night to support skin renewal. 

3. Vitamin C and AHAs/BHAs 

The acidic pH of AHAs or BHAs, such as glycolic, lactic, and salicylic acid, can destabilize vitamin C, reducing its effectiveness. Used in combination, vitamin C and exfoliating acids can lead to skin irritation. Dermatologists advise to apply them at different times of the day. For example, use vitamin C in the morning for its antioxidant properties and acids at night. Or, alternate the days when you use these products. 

4. Niacinamide and Vitamin C 

Niacinamide usually pairs well with other actives. However, there is no consensus on the effects of interaction of niacinamide with vitamin C. More data is needed to elucidate whether niacinamide reduces the effectiveness of vitamin C. Further, the combination may increase skin irritation or facial flushing. 

If you notice skin irritation, or want to be safe and maximize these ingredients’ individual benefits, use them at different times of the day. Apply vitamin C as part of your morning skincare routine and niacinamide at night.

5. AHAs or BHAs and Sunscreen

Exfoliating acids pair well with hydrating humectants and emollients, as well as with anti-inflammatory niacinamide. Exfoliating acids can increase skin sensitivity to the sun, elevating the risk of sun damage, which is why dermatologists recommend using them at night. Never skip sunscreen and opt for an SPF of at least 30 to provide adequate protection. 

Designing a Skincare Routine That Works 

Introduce new products slowly and observe how your skin responds. Consulting with a dermatologist is always a good idea, especially if you want to introduce new active ingredients into your skincare routine. 

To design a skincare routine that incorporates active ingredients, you can use the following general principles. 

  • In the morning, apply vitamin C serum and always follow up with sunscreen. 
  • At night, use an effective but gentle cleanser, such as Skincare JunkieⓇ Gentle Jelly Facial Cleanser, to lift away makeup and/or sunscreen. 
  • Apply retinol or products containing AHAs/ BHAs, such as Skincare JunkieⓇ Pore Therapy Daily Toner Pads, on alternating nights if you are new to these ingredients. 
  • If you apply niacinamide, experiment using it with retinol or AHAs/ BHAs, or alternate the days when you apply them. 
  • Always patch test new products containing active ingredients. Introduce one active at a time into your routine and observe how your skin responds over 3-7 days. If you experience irritation, stop using active ingredients and consider consulting a dermatologist.