What Not to Mix with Vitamin C Serum (And What Works Best)

Vitamin C is powerful—but it’s not always compatible with every ingredient in your routine. Here’s what to avoid and what pairs well with it.

Ingredients to Avoid Mixing with Vitamin C:

• Benzoyl Peroxide

  • Why? It can oxidize vitamin C, making it less effective.

  • Solution: Use benzoyl peroxide in a different routine (e.g., vitamin C in AM, BP in PM).

• Benzoyl Peroxide: May deactivate Vitamin C.

• High-pH Products (e.g., Alkaline Cleansers)

  • Why? Vitamin C (especially L-ascorbic acid) works best at a low pH (3.5 or lower). High-pH products can neutralize it.

  • Solution: Apply vitamin C on clean, dry skin before higher-pH products.

• AHAs/BHAs: Using too many exfoliants can over-sensitize skin.

Ingredients That Work Well With Vitamin C:

• Hyaluronic Acid: Boosts hydration and soothes skin.

• Niacinamide (if well-formulated): Can brighten and balance.

• SPF: Essential to protect your skin after applying Vitamin C.

Best Combinations with Vitamin C:

✔ Hyaluronic Acid – Boosts hydration
✔ Vitamin E – Stabilizes and enhances vitamin C
✔ Ferulic Acid – Increases antioxidant protection
✔ SPF (Sunscreen) – Vitamin C boosts sun protection

Final Tip:

If you’re unsure, apply vitamin C in the morning and use other actives at night. Always patch-test new combinations!