You can use Lotion P50 and Vitamin C, but not together. Both are highly active, low-pH formulas that can irritate or cancel each other out. Space them out: P50 at night, Vitamin C in the morning, or alternate days.
This ensures results without triggering sensitivity; otherwise, you might end up with irritation or dulled results. We see this mistake often, but the fix is simple.
With a few tweaks to your routine, you can safely reap the full benefits of both actives.
This article walks you through how to do it, without compromising your skin barrier or investment.
Can You Use Lotion P50 And Vitamin C In The Same Routine?
You can, but not in the same session.
Vitamin C, especially the pure kind, L-ascorbic acid, is a phenomenal antioxidant. It brightens, firms, protects, and just makes your skin look awake.
But it’s picky. It needs a slightly acidic pH (around 3.5) to stay stable and work properly.
Now enter Lotion P50. This isn’t your average toner.
It’s a skin-refining powerhouse, filled with AHAs, BHAs, PHAs. Its pH sits even lower, often closer to 3.0 or below. That’s more exfoliation, more intensity, and more risk when combined with other actives.
Why They Clash
Here’s the chemistry:
Low pH + Low pH = Skin Freak-Out. The combo can overwhelm your barrier. Clients who layer the two often end up red, dry, or breaking out.
Niacinamide vs. Vitamin C: Many P50 formulas include niacinamide, which, when layered directly with ascorbic acid, can reduce both of their benefits.
Acid overload: You’re stacking actives that don’t need to be stacked. P50 already preps your skin like no other, it doesn’t need the competition.
Stability issues: P50’s acids can actually oxidize your Vitamin C serum, rendering it less effective, or worse, irritating.
How I Recommend Using Both
You can use both, just not together. Here’s what works for most of my clients:
Vitamin C in the morning, always under SPF. This is your antioxidant shield for the day.
Lotion P50 at night, after a gentle cleanse, so it can work its exfoliating magic while you sleep.
Alternate mornings: If your skin’s on the sensitive side, try Vitamin C one day and P50 the next.
Buffer your actives: Give it at least 30 minutes between the two if you’re trying to layer, but honestly, why force it?
Remember, skincare isn’t about doing more. It’s about doing the right things in the right order. That’s where the magic happens.
What to Use with Vitamin C If You Love Biologique Recherche
I get it, once you fall in love with Biologique Recherche, there’s no going back. But not everything in the BR line plays well with it. Especially not P50.
Don’t worry, you don’t have to give up your BR favorites.
Here are my top five Biologique Recherche products that complement your Vitamin C routine without clashing, all tested, loved, and used by me personally:
1. Masque Biosensible
This is the calm your skin craves. After Vitamin C (which can be a bit zingy), this mask delivers pure comfort.
It's packed with soothing ingredients like cucumber and fatty acids that reduce inflammation without interfering with your active serums. I love using it on travel days or post-peel weeks.
2. Crème Masque Vernix
Inspired by the protective coating on newborns’ skin, it’s a rich, multi-use cream-mask hybrid that restores and protects fragile skin.
After Vitamin C, this seals in the glow while reinforcing the barrier, especially helpful in colder seasons or dry climates.
3. Serum Biosensible
If your skin is sensitive or has been over-treated (it happens!), this serum is your rescue team. It hydrates and rebuilds the barrier. After Vitamin C, this locks in moisture without interfering with the actives.
It’s a staple in every routine I design for clients just starting with acids or retinoids.
4. Masque Visolastine+
Think of this as a tall glass of water for your face. It’s intensely hydrating and helps maintain the suppleness that Vitamin C can sometimes strip away.
Use it 2–3 times a week for long-term hydration and glow insurance. I like applying this after flights or beach days.
5. Emulsion Originelle Régénérante
Rich, calming, and absolutely luxurious. It has essential fatty acids and botanical extracts that deeply nourish without suffocating the skin.
After your Vitamin C serum, this seals everything in, keeping your skin soft, plump, and protected.
6. Creme ISO-Placenta
Iso-Placenta is a go-to if you’re using Vitamin C to even out tone or fade post-acne marks. It calms inflammation, speeds up healing, and layers seamlessly under SPF. I often pair it with Vitamin C in the morning for brightening and regeneration without irritation.
From Confused To Confident, Our Clients Know What Works
When it comes to skincare, confusion is expensive, and damaging. People come in with redness, peeling, or zero results, and the problem almost always boils down to this: too many actives, layered without intention.
KarinaNYC builds personalized routines that make sense for your skin, your lifestyle, and your goals. If you're investing in actives like Lotion P50 and Vitamin C, you deserve to see the glow, not the irritation.
When You’re Done Guessing, Karina Has The Answer
If you’re here, chances are you’re trying to unlock the power of advanced actives like Lotion P50 and Vitamin C without blowing up your skin barrier in the process.
You’ve probably felt the frustration of:
❌ Redness or peeling after layering “the wrong way”
❌ Products that cancel each other out instead of complementing each other
❌ Advice overload from influencers who’ve never seen your skin in person
Here’s what I do differently:
🧴 Free Skin Consultation
Let’s get you matched with the right P50 formula and the best Vitamin C for your skin’s actual needs, not what’s trending. No guessing. No stress.
✨ Hand-Tested Product Curation
Everything we sell, I’ve used. My clients get real results because we only stock skincare that’s potent, fresh, and stored properly. No expired bottles. No heat damage. No third-party gamble.
💆♀️ In-Clinic Treatment Plans
Take your results even further with facials designed to enhance your home routine. Every treatment is built around your skin goals, whether that’s glow, firmness, or clarity.
Ready to stop experimenting and start transforming? Let’s get you glowing.
