A French Hairstylist Told Me to Use P50 on My Scalp, so I Tried It for Two Months

On October 17, 2024, I had the best hair day of my life.

My roots felt airy and fresh; my tapered, stringy ends looked bouncy and full (despite delaying a trim for yet another three weeks—oops); and my color appeared ten times more vibrant. All I did was saunter over to NYC's Paul Labrecque Salon & Skincare Spa for a casual (read: very extensive), multi-step scalp treatment with pro hairstylist Frederic Moine, who focused on a French skincare staple—Biologique Recherche's Lotion P50.

Those familiar with the cult favorite exfoliator might (understandably) raise a brow. How can this vinegar-smelling solution possibly help with hair? Well, allow me to reveal that P50 comes in a scalp version—called Lotion P50 Capillaire—that helps balance oil production, reduce flaking, and stimulate the skin up top. Since Moine taught me how to properly massage it into my scalp (which was an experience nothing short of marvelous, let me tell you), my hair has never looked healthier. I'm currently two-ish months into the routine, and the commitment has been well worth it. Allow me to gush about my latest winter haircare savior.

Wait, what's P50?

For the uninitiated, let's begin with a quick download of the beloved Biologique Recherche staple. Lotion P50 is an exfoliating toner that works wonders for fading hyperpigmentation, smoothing skin texture, and brightening overall tone. In addition to standard skin-buffing heroes like lactic acid, salicylic acid, and malic acid, it contains some unconventional players like onion extract, horseradish extract, myrrh, myrtle, and vinegar for extra purification. This is why P50 has a reputation for a funky, salad dressing-like smell (some can't get past it, but I honestly don't find it too distracting!).

Biologique Recherche has launched multiple versions of the classic since its inception, including a targeted formula for dry skin, sensitive skin, and those struggling with hyperpigmentation. And in skincare circles, P50 has become a household name, lauded by derms, aestheticians, and celebrities alike for its smoothing, clearing properties. The general consensus? It's pricey—but it's worth it.

How to Use It on the Scalp

As I mentioned up top, P50 also comes in a scalp-focused solution, dubbed Lotion P50 Capillaire. It contains the same core ingredients as the aforementioned skincare savior, like AHAs and BHAs, but it also features specific, good-for-scalp actives, such as rosemary extract and niacinamide. Not to mention, it contains garlic bulb extract (which research shows can help with hair growth) and vinegar, which has purifying properties. Given those pungent actives, P50 Capillaire also has an acidic scent that doesn't exactly lend itself to a soothing spa day, but not to fret—it works best as a pre-shampoo treatment.

Simply section your hair and apply the tonic until your scalp is evenly coated, massage it gently with your fingertips, then let it marinate for about five to 10 minutes. (Like the toner, you might experience a slight tingly sensation with P50 Capillaire.) Once all those purifying, nourishing ingredients have properly soaked in, you can hop in the shower and shampoo and condition your strands as normal.

My Experience and Results

I don't have capital-D dandruff, but I'd be lying if I said I didn't accrue itching and flakes once the air turns crisper. (Maybe that means I do have moderate dandruff? Derms, weigh in!) As soon as I implemented P50 Capillaire into my routine, however, those side effects quickly started to ebb. Even just applying the solution on my scalp gave me immediate relief, the tingly formula instantly refreshing my senses.

But let me back up for a moment. In Moine's chair, I was given a full-on scalp detox treatment that lasted around one and a half hours. He first used a pipette to precisely apply the P50 solution all over my scalp before giving me a lovely, 10-minute head massage, during which I could literally feel the tension melting from my body. After said bliss, I skipped over to the wash bowl, where Moine scrubbed out all the buildup and overall gunk the P50 brought to the surface. I'll admit, it was strangely gratifying to see those white flakes swirling down the drain.

Next, he applied the brand's Masque Dermo-Apaisant, another pre-shampoo mask meant to calm any inflammation—sort of like how a facialist might apply a cooling, moisturizing mask post-chemical peel to neutralize the effects. Then I headed back to the wash bowl, where Moine shampooed and deep conditioned my strands (using Biologique Recherche products, of course). Before blow-drying, he gave my lengths a healthy spritz of the brand's Keractive treatment to strengthen the hair fiber, smooth the cuticle, and provide shine. My hair has never looked glossier, smoother, or healthier—and it all started with some scalp T.L.C.

Now, I'd be lying if I said I followed this exact same routine for the next two months. I've got things to do! People to see! Dedicating 10 minutes to weekly scalp massages doesn't sound like a huge commitment, but after a particularly long work day, even 60 seconds can feel like a giant undertaking.

Yet even without the spa-grade relaxation, P50 Capillaire gave me that same level of scalp-refreshing bliss. I shampoo my hair one to two times per week, so I make sure to give my scalp a good spritz each wash day. I don't use a pipette like Moine; rather, I section my hair and apply P50 to each, massaging it in with my fingers before moving onto the next area. Once my scalp is thoroughly coated, I'll use a scalp brush for some extra stimulation, massaging all over in circular motions. The whole process takes no more than five minutes. After leaving it to marinate for around 10 minutes, I then hop in the shower and shampoo and condition as normal.

I'm currently two months into the routine, and I won't ever look back. My 2C waves air-dry to perfection—soft, smooth, and bouncy—and most importantly, my scalp feels comfortable, nary a flake in sight. Considering the frigid temperatures we've experienced in NYC lately (it's a balmy 15 degrees as I type this), that's an impressive feat. Now, whenever a friend or colleague asks me if I'm a P50 fan (as I said, it's a household name!), I respond with: Yeah, the toner is great, but I think it works even better on your scalp. Call it a French haircare secret.

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Opening Image: @jamieeschneider