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Kerastase

Kerastase Genesis Hair Serum – Daily Strengthening Treatment

  • Based on 11,639 reviews
Condition: New
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Availability: Only 5 left in stock, order soon!
Fulfilled by Amazon
Arrives Sunday, Oct 18
Order within 14 hours and 26 minutes
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Size: 1 Fl Oz (Pack of 1)


Features

  • Fortifiant Hair Serum: A daily strengthening serum designed to prevent hair fall due to breakage from brushing. Enriched with ginger and caffeine treatment improves resistance in weak brittle hair
  • Benefit: After use, 97% experience less hair fall due to breakage from brushing. Serum fortifies & strengthens to create nourished & healthy hair. Lightweight formula that will not leave residue
  • Additional Benefits: Contains Arginine, an ingredient that helps stimulate healthy hair by supporting strong blood flow to the root of hair cells. Can be targeted to areas with less density
  • Suggested Use: Use morning or evening for a minimum of 6 weeks. Apply 4 doses on dry or towel-dried scalp section by section. Massage to promote distribution and absorption into hair. Do not rinse.
  • Genesis Collection: Use with Bain Nutri-Fortifiant Shampoo, Fondant Renforcateur Conditioner, and Defense Thermique Primer for nourished healthy-looking hair with reduced breakage. Ideal for normal to dry weakened hair.

Description

Our hair care collection that treats hair fall due to hair breakage from brushing. The Genesis collection is a dual action fortifying system professionally formulated to strengthen hair and reduce hair breakage. Expert Formulas Fusio-Dose Instant Transformation, Infinite Possibilities. In-Salon Service Make an appointment in your Kérastase salon for a personalized hair diagnosis. Will this make my roots greasy? The Serum Fortifiant is a silicone-free, lightweight formula designed to absorb quickly into the scalp without leaving residue or oiliness. How much should I use per application? Fill the pipette to the black dosage line. This equals one dose. We recommend using 4 doses to cover the entire scalp. Can I use this on dry hair? Yes, the serum can be applied to both towel-dried hair after washing or dry hair on non-wash days. PROFESSIONAL HAIRDRESSERS: Kérastase is a leading global luxury professional haircare brand. Born in Paris in 1964, the brand has built its reputation on delivering exceptional performance on scalp and hair through exquisite products and personalized, in-salon treatments, all powered by scientific expertise. Kérastase adopts a care-first philosophy to care for all hair types and all individuals, as well as the world we live in.

Package Dimensions ‏ : ‎ 4.13 x 1.54 x 1.46 inches; 3.67 ounces


Manufacturer ‏ : ‎ Kerastase


Best Sellers Rank: #1,314 in Beauty & Personal Care (See Top 100 in Beauty & Personal Care) #22 in Hair Loss Products


#22 in Hair Loss Products:


Customer Reviews: 4.5 4.5 out of 5 stars (11,639)


Brand Name: KÉRASTASE


Item Highlight: Serum fortifiant, nourishes and reinforces, anti-breakage, silicone-free, for weak hair


Unit Count: 1 Fluid Ounces


Number of Items: 1


Manufacturer: Kerastase


Hair Type: All


Product Benefits: After use, 97% experience less hair fall due to breakage from brushing. Serum fortifies & strengthens to create nourished & healthy hair. Lightweight formula that will not leave residue.


Item Form: Drop


Scent Name: Warm solar notes, mandarin, freesia, and patchouli.


Special Ingredients: French Camellia Oil


Material Features: Refillable Packaging


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, Oct 18

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews

    • Worth every cent
Review Image by Thao Ngo
I had very high expectations for this serum because of its price and well known brand. Kerastase is luxurious and i expected a feminine scent but it actually ends up smelling like men’s scent which is not a big deal to me because what matters most is that it works wonderfully. I’ve always been insecure about my hairline and thinness, i thought wearing wigs was the only solution to change my insecurity. Ive used this first big bottle for only half way through everyday after washing and I can already notice a big change. My hair looks fuller when its fresh (after washing and dried) and it doesnt get oily after a few hours like before. I feel like a new woman, (i also get noticed a lot) ... show more
Reviewed in the United States on August 22, 2026 by Thao Ngo
    • Excellent
Size: 1 Fl Oz (Pack of 1)
I really love this Kérastase hair serum! It makes my hair feel softer, smoother, and healthier without making it feel heavy or greasy. It also helps control frizz and leaves my hair looking shiny and well cared for. I have noticed a difference in the overall appearance of my hair since I started using it. A little goes a long way, and the scent is amazing. Definitely a great addition to my hair care routine! ... show more
Reviewed in the United States on September 5, 2026 by Isairis Cordero Cabrera
    • It works for shedding
Size: 1 Fl Oz (Pack of 1)
I am a fan of this serum for shedding. Im not sure it works for anything else but I have noticed that my hair does not shed as much anymore. I use it at night before bed. It also makes my hair smooth and shiny. It smells good but has a strong specific smell so I could be off putting for some. it is very expensive for what you get and you use a lot. I would only purchase on sale or with a discount. ... show more
Reviewed in the United States on May 21, 2026 by Laura Maness
    • The Only Hair Product That Actually Worked for Me
Review Image by Gabriela K.
Review Image by Gabriela K.
I’m not usually the type of person who writes reviews for products I order, but I really wanted to share my honest experience. Postpartum completely damaged my hair, and I was desperate to find something that actually worked. I tried Nutrafol and took it consistently for three months, but nothing changed. It felt like a waste of both time and money—and honestly, I hated the taste too. If you’re thinking about trying argan oil, rosemary oil, or any of those “magic” hair growth oils, I’ll say this: if you’re prone to oily roots like I am, you’re probably not going to like them. I hate the feeling of oily roots, so putting oil on my scalp was never something I could stick with. I’m currently on my second bottle of this serum, and when my sister asked me, “What are you doing to your hair?” I went back and looked at my before-and-after photos. I was shocked—I didn’t even realize how much new hair growth I had. My hair looks so much denser, healthier, and thicker, and it smells soooo good. I’m obsessed with the scent, and I’ve been getting so many compliments. I use it almost every day, and one bottle lasts me about a month and a half. It is a bit pricey, but I’m honestly tired of wasting money on random $20–$30 products that don’t work. I will always recommend this product to every girl I know. I comment under posts, reels—anything about hair treatments—and recommend this product to anyone. ... show more
Reviewed in the United States on December 14, 2025 by Gabriela K.
    • Amazing Hair Serum – Noticeably Stronger and Healthier Hair!
I’m very impressed with this Kerastase Genesis Hair Serum. It feels lightweight, absorbs quickly, and doesn’t leave my hair greasy or heavy. After using it consistently, my hair feels stronger, softer, and looks healthier overall. I especially noticed less breakage and my hair feels more nourished and manageable throughout the day. It also adds a beautiful natural shine while helping reduce dryness and frizz. The formula feels luxurious and a little goes a long way. This is a great daily treatment for weak or damaged hair and fits perfectly into a hair care routine. Definitely worth trying if you want stronger-looking, healthier hair with a salon-quality feel! ⭐⭐⭐⭐⭐ ... show more
Reviewed in the United States on June 19, 2026 by Darcy
    • This product works!
I have never felt compelled to write a review before, but this product has made me have a change of heart. Bottom line, this hair serum works and delivers everything as promised. I have always been insecure about my hair line framing the edges of my forehead; I believe the cause is from years of wearing tight hair-dos for sports, every day styles, etc. I purchased this serum before my wedding in October and have been absolutely blown away by the results. I can see noticeable growth in the areas of concern and can feel a major difference in the texture of my hair, thickness, and even length. I've also noticed a significant reduction in hair breakage around my face and an increase in shine! I have been getting compliments about how healthy my hair looks! I was a little hesitant about the price, and the $60+ price is the reason I'm giving this a 4/5, but would now recommend this to anyone looking to restore hair growth or wanting to improve overall hair health. Stay consistent with the application and you will see some serious results! ... show more
Reviewed in the United States on February 17, 2026 by Amazon Customer
    • Best product- worth the price!
My favorite hair product. Repurchase multiple times. I’ve used this during pregnancy and postpartum to help with hair fall. Will never let it run out! Expensive but worth it for long term results.
Reviewed in the United States on August 4, 2026 by Emily Terry
    • Lightweight oil, good on oily scalp
Size: 1 Fl Oz (Pack of 1)
I like this oil. I use it on my scalp overnight. I have an oily scalp so I was nervous about using this. It does not make me more oily. I don’t think I’ve used it long enough to see any difference but I’m hopeful. It seems like it absorbs well and it does not feel heavy at all. I don’t have thin hair so I can’t speak for that group. I have long hair that is medium thickness and thick (density). I bought this because of hair thinning as I get older. It makes my scalp feel nice and it smells great ... show more
Reviewed in the United States on September 28, 2026 by Christine

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