Serum Extentioniste is a highly concentrated hair serum designed as a scalp treatment to promote a healthy scalp.
This scalp treatment is enriched with Ceramides that stimulate the growth of strong healthy hair follicles. Serum Extentioniste also acts as a hair straightening serum to add smoothness and softness to hair. A hair serum created to reinforce roots, purify and protect the scalp while promoting a healthy scalp environment.
Apply maximum 3 pipettes of Serum Extentioniste along all the scalp, once or twice a week.
Using the tips of the fingers, work the Serum into the scalp, using circular motions.
Rating & Reviews
Emma H
51.776808813E12 21/04/2026
Amazing for length!
I was focused on growing my hair after a bad haircut and this did the trick! I saw great length within months and the bottle lasted around 3/4 months using it 2x a week after washing my hair! I prefer this over the Gensis growth serum - can’t recommend enough!
Originaly posted on kerastase-usa.com
ExtentionisteSerumLover
51.776808813E12 21/04/2026
I love this product
[This review was collected as part of a promotion.] I have been using this product after every wash and my hair has gotten visibly thicker and unlike a lot of products, this one does not make my scalp itch.
Originaly posted on kerastase-usa.com
Lolo70
51.776662107E12 20/04/2026
Love it
Hoping this will help with length. Trying to grow down back. Will update after a year. Smells nice hair lovely soft.
Originaly posted on kerastase-usa.com
EmFalk
51.776207607E12 14/04/2026
Love it
[This review was collected as part of a promotion.] This serum helped with my dry scalp, without creating a heavy feeling on my hair
Originaly posted on kerastase-usa.com
Arr123
51.775965505E12 11/04/2026
Great Product!
I used the product as the directions said, and I truly feel the product made a difference in my hair. Definitely planning to repurchase as the product made my hair longer and somehow enhanced my waves as well!
Originaly posted on kerastase-usa.com
Natashamaria1
51.776116713E12 13/04/2026
SaraUT
51.775148315E12 02/04/2026
Yes! Just yes!
I love this serum! It takes a couple of months to see results but those results are unmatched! Do yourself a favor and get this serum!
Originaly posted on kerastase-usa.com
cookie2727
31.776355217E12 16/04/2026
Decent/Mid
Ive been using this product for 3months, I haven't seem much change in my hair. but it doesn't leave my hair oily. Hopefully we see results within 6months
Originaly posted on kerastase-usa.com
Reply from Consumer Care Center 27/03/2026
Thank you for your patience and consistency over the last three months! We are so pleased to hear that the formula is integrating beautifully without weighing your hair down. At Kérastase, we believe true hair transformation is a journey, and we are optimistic that with continued care, you’ll begin to see the radiant results you’re looking for by that six-month mark. We’re cheering for your hair’s progress!
Parvinder Kaur
51.774993249E12 31/03/2026
It actually workedddd!!!!!!
I used everything but nothing worked. this was my last option but this one worked. In just a weeek my hairfall was reduced. this is worth of price. Ive been recommending this to my every singlw friend.
Originaly posted on kerastase-usa.com
duckieduckerz
51.776012246E12 12/04/2026
Using for 6-7 years - totally transformed my hair.
[This review was collected as part of a promotion.] The only downside of this product is that it’s increased in price over the years, but of course, I’m still gonna buy it. I couldn’t grow my hair past my shoulders for years. Out of all the products I’ve tried (some left, some kept), this is the product that’s done the most for my hair. I wish I could afford to buy all Kerastase products!
Originaly posted on kerastase-usa.com
Emily07268
51.774993276E12 31/03/2026
Amazing product
[This review was collected as part of a promotion.] Finished a whole bottle of this product and just ordered my second. Takes a few weeks of consistent use to notice a difference, but it has definitely made my hair way thicker and stronger. Will be buying this product again!
Originaly posted on kerastase-usa.com
AbbyAA
51.774993284E12 31/03/2026
Hair feels great and healthier
I like using this in combo with the genesis serum. I feel like the two products work so lovely together, strengthening existing hair while also allowing for new growth. Love the way it feels and will continue to use
Originaly posted on kerastase-usa.com
Pixie7720
51.774993293E12 31/03/2026
Stronger, Healthier Hair
I love the Kérastase Resistance line. It’s made my hair feel stronger, smoother, and much healthier with noticeably less breakage. A little goes a long way and it doesn’t weigh my hair down. Definitely worth it if your hair needs repair. ✨
Originaly posted on kerastase-usa.com
JoDeeDee
51.774993302E12 31/03/2026
Growing baby hairs!
[This review was collected as part of a promotion.] I apply this to the balding part of my scalp and then use a scalp massager for several minutes. My balding spots are growing hair - I never thought this would happen!
Originaly posted on kerastase-usa.com
DomciaS
51.772842509E12 06/03/2026
Great serum that doesn’t leave scalp oily
Wonderful serum, to my surprise it doesn’t leave hair looking oily which is such a positive. My hair feels healthy and I can see it growing. This helped me get some length
Originaly posted on kerastase-usa.com
Katherine05
51.772428507E12 02/03/2026
Great one
[This review was collected as part of a promotion.] This is a great product for your hair I ever using it since last September really good
Originaly posted on kerastase-usa.com
Vartan
51.772336708E12 28/02/2026
It works!!
[This review was collected as part of a promotion.] I am beyond impressed with the results! I’ve already started noticing new hair growth, which is such an amazing feeling. The baby hairs are coming in and everything feels healthier and stronger overall. It’s clear that the treatment is actually working.
Highly recommend to anyone looking for real results. 💛
Originaly posted on kerastase-usa.com
BWildMama
51.774993328E12 31/03/2026
Healthy Roots!
This product does an amazing job at strengthening and lengthening my hair. When I use it regularly I notice a difference in the amount of hairfall that I get as well as the overall quality and thickness of my hair. This is a must in my haircare routine!
Originaly posted on kerastase-usa.com
Kikibeme
11.771818308E12 22/02/2026
I’m not impressed
I’ve been using for a few weeks & not loving this product. I prefer the hair oils I’ve purchased. I stopped using as it gives my scalp a build up.
Originaly posted on kerastase-usa.com
Reply from Consumer Care Center 20/02/2026
We completely understand your affection for our iconic oils, which provide that signature sublime shine, but we are concerned to hear about the buildup on your scalp. This sensation often arises when a formula is too lipid-rich for your scalp's specific ecosystem, causing the active ingredients to accumulate rather than clarify the fiber. For your fine hair, we recommend experiencing our Genesis range, which is expertly formulated to deeply cleanse and fortify the scalp while providing the lightweight strength and volume you desire. By focusing your oil ritual strictly on the mid-lengths and ends and utilizing a more clarifying Bain for your scalp, we are confident we can achieve that perfect balance of purification and luxurious care that defines the Kérastase experience.
Noemie007
51.771403522E12 18/02/2026
Produit exceptionnel c'est pour ca en ruptureu
The author has not written a review.
Originaly posted on kerastase.fr
Jason D
51.772036112E12 25/02/2026
Incredible product
Wish this came in a bigger bottle! It has become a part of my regular routine. Great for hair that blow dries and uses lots of product.
Originaly posted on kerastase-usa.com
Hairenthusiast04
51.774993344E12 31/03/2026
AMAZED
[This review was collected as part of a promotion.] I used this product everyday after washing my hair. Yes, I washed my hair everyday in the matching shampoo and conditioner. I experienced tremendous growth. I got my hair trimmed before I started using the product and I have at least grown two inches since October.
Originaly posted on kerastase-usa.com
Fatima13
41.770843615E12 11/02/2026
Good product
Makes my scalp skin feel fresh and smells pretty good.
Originaly posted on kerastase-usa.com
Jessica83
41.770417909E12 06/02/2026
Love this stuff it’s so good
Makes my hair so strong it really helps the overall feel of my hair
Originaly posted on kerastase-usa.com
Mefab1
51.769809511E12 30/01/2026
Could see a difference in 2 weeks
[This review was collected as part of a promotion.] After just 2 weeks use my hair is shinier and has more body. Hopping to see growth very soon
Originaly posted on kerastase-usa.com
Mary Beth O
51.769698811E12 29/01/2026
Kerastase Krazy
I love this product. I use exclusively Kerastase hair products. I feel that my hair looks better than ever thanks to the regimen I am on.
Originaly posted on kerastase-usa.com
Elizabeth2719
51.770498907E12 07/02/2026
Great product!!
Great product!! Love to use and makes my hair feel amazing.
Originaly posted on kerastase-usa.com
Wonder
51.769267713E12 24/01/2026
Absolutely works!!
I’ve had so much new growth with this serum! It just takes a little; I only use it on the front half of my scalp, to help with breakage. I have quite a bit of hair, but a very fine strand. It doesn’t make anything greasy, or oily. I despise the cost, but continue to buy it because it works!
Originaly posted on kerastase-usa.com
Dima abuobead
51.772945149E12 07/03/2026
Perfect for hair fall will buy it again for sure
I’m using it after hair bath with wet hair 3 times a week
Originaly posted on kerastase-usa.com
Peppster
11.768589327E12 16/01/2026
Too much fragrance irritates scalp
I’ve been using kerastase products for a while now - I really hate how they overly scent leave in products. This made my scalp worse, irritated, and a hundred times worse. I even tried it for a few days, thinking that it was just winter making this happen. I’m so disappointed in this product. Had the same experience with the miracle overnight serum too.
Originaly posted on kerastase-usa.com
Reply from Consumer Care Center 16/01/2026
We are sorry to hear about the experience you had with Resistance Extentioniste Scalp & Hair Serum. We would like to speak with you directly about it. Please give us a call @ 1-877-254-9949 for assistance and provide the case # 44842874. Looking forward to speaking with you. It would be helpful if you could have the product available when you call.
Jodi E
51.768498215E12 15/01/2026
Easy to use and not greasy.
[This review was collected as part of a promotion.] Easy to use and not greasy. It’s easy to apply with a subtle, but nice scent.
Originaly posted on kerastase-usa.com
Yaidery85
51.768148116E12 11/01/2026
Serum
[This review was collected as part of a promotion.] I just got ,I can’t say much about it I would like to receive my rewards point without need to write a review ,I spend a lot of money 💵
Originaly posted on kerastase-usa.com
Paola P
51.767968128E12 09/01/2026
Love!!
I love how I can apply it and it doesn’t weigh the hair down nor does it make it greasy
Originaly posted on kerastase-usa.com
Rosmery025
51.767968128E12 09/01/2026
Great product
[This review was collected as part of a promotion.] My hair is stronger and softer after using this product
Originaly posted on kerastase-usa.com
shalomcharlie
51.767314705E12 01/01/2026
This is the best serum for my hair….. I am Picky
Absolutely the l best! So glad I bought it! Shiny healthy growing long hair!!!!
Originaly posted on kerastase-usa.com
natulya07
51.767378614E12 02/01/2026
Hair Serum
Loved how it smeels and makes my hair so manageable and healthy looking after blow drying
Originaly posted on kerastase-usa.com
Mrsp25
51.767378614E12 02/01/2026
Lengths for days
Talk about getting your hair wedding ready. Noticeable change in growth after start of use. Adding to my repeat orders!
Originaly posted on kerastase-usa.com
Ari1989
51.766587509E12 24/12/2025
the best serum for growth and strength
This is my 3rd purchase, it's excellent, I've seen the results it promises.
Originaly posted on kerastase-usa.com
Elizabethb843
51.766457905E12 22/12/2025
Great product
The scalp and hair serums from Kerastase are AMAZING as a whole. I was using the gold bottle before. Both have great benefits.
Originaly posted on kerastase-usa.com
Mila21
51.766281507E12 20/12/2025
My favorite
This is the most wonderful product ever used I recommend it 100%
Originaly posted on kerastase-usa.com
Jessica273
51.765602437E12 13/12/2025
Great and non-greasy
So far I’m seeing a lot of new growth, I’m on my second bottle. This absorbs so well and doesn’t leave the scalp greasy.
Originaly posted on kerastase-usa.com
Stacy11111
51.765602441E12 13/12/2025
Love this
I started using this for itchy ‘gluten’ scalp. It worked after only 2 weeks and I was so so so thankful. What a win!
Originaly posted on kerastase-usa.com
Grod646
51.764734406E12 02/12/2025
I love it
I love this hair line. I noticed improvement on my hair immediately after the very first use. This is my first time using Karastase hair products and I honestly think I found the one
Originaly posted on kerastase-usa.com
Beth24
31.763664204E12 20/11/2025
Not sure
[This review was collected as part of a promotion.] I couldn’t really see a difference in my hair. Didn’t strengthen as far as I could tell.
Originaly posted on kerastase-usa.com
Reply from Consumer Care Center 20/11/2025
Hello. We're truly sorry to hear that you didn't experience the strengthening benefits you were looking for with our product. We understand how frustrating it can be when a product doesn't deliver the results you expect, and we sincerely apologize for your disappointment. We're always striving to create effective solutions for healthy hair, and feedback like yours is incredibly valuable as it helps us understand our customers' experiences.
Meghan F
51.765602511E12 13/12/2025
I must have serum to protect long hair
I have been trying to grow my hair out for the past two years and I love this whole line because it’s meant to help preserve medium to long hair and it is divine. I love the texture of the serum and I love how smooth it makes my waves. This product is a must have if you’re trying to grow out hair that’s long to avoid breakage.
Originaly posted on kerastase-usa.com
Missy T
51.769450425E12 26/01/2026
Reduces Flake
[This review was collected as part of a promotion.] I don’t normally get a dry too much scalp but I find myself washing my hair more often and using this serum to prevent flake. I haven’t seen flakes in a year since using this
Originaly posted on kerastase-usa.com
radontheelement
51.762011445E12 01/11/2025
hair feel smooth and soft
I use it on my hair and hair tips to prevent split ends. so far so good. smells good and the hair feels smooth and soft
Originaly posted on kerastase-usa.com
Hannah35
51.765602575E12 13/12/2025
Amazing product
Makes my hair soooo soft and healthy. Will definitely be a repeat customer.
Originaly posted on kerastase-usa.com
Gala2025
51.761324311E12 24/10/2025
Stronger hair
I’ve been using this serum for a few weeks now, and I can honestly say my hair feels stronger and healthier. It’s lightweight, absorbs quickly, and doesn’t leave any greasy residue. I love that it focuses on the scalp, not just the end, it really makes my roots feel refreshed and balanced. I’ve noticed less breakage and my hair seems to be growing a bit faster. The only downside is the price, but a little goes a long way, so I think it’s worth it for the results.
Originaly posted on kerastase-usa.com
kerastaselover72
41.76417454E12 26/11/2025
Nice texture, bad dropper
I love everything Kerastase, so this time around I decided to try this serum. While I love the texture, I'm not loving the dropper as it doesn't hold the serum inside, and when you pull it out of the container it leaks, and it's a waste of product. On the other hand, I haven't seen much results to be honest but I need to give it more time. Still, Kerastase is my number 1 go-to brand for every hair-related need.
Originaly posted on kerastase-usa.com
AnneHa
51.759189505E12 29/09/2025
Love it!
[This review was collected as part of a promotion.] I have noticed a considerable difference in the strength of my hair since incorporating this product. I use this in the am and the growth serum at night!
Originaly posted on kerastase-usa.com
Zuly89
51.758165307E12 17/09/2025
Amazing
[This review was collected as part of a promotion.] Make my hair stronger and healthier. My hair is so long and shiny. I love it. And I recommend it
Originaly posted on kerastase-usa.com
Mon347
51.759035604E12 28/09/2025
Amazing
My favorite thing is the smell! This product makes my hair smell great all day, I have noticed a difference in my scalp and hoping for longer and stronger length
Originaly posted on kerastase-usa.com
Mari2789
51.757861109E12 14/09/2025
Impressive
It really works i used the line complete
Just to make sure
Originaly posted on kerastase-usa.com
Anna Liza
51.75761991E12 11/09/2025
Great product to add in your regimen
It is a great buy- will regularly buy this one for sure
Originaly posted on kerastase-usa.com
Aga2025
51.757295905E12 07/09/2025
Best serum ever
I used on my colored hair. My hair are healthy and growing
Originaly posted on kerastase-usa.com
ZIANELKA
51.75691431E12 03/09/2025
I love it
Totally recommend !! Hand up !! I been using this for about 3 months and definitely see improvement.
Originaly posted on kerastase-usa.com
Liv DG
51.756868906E12 02/09/2025
Amazing
[This review was collected as part of a promotion.] Love it! I’ve definitely noticed a difference and it smells really good! It also doesn’t leave your hair feeling greasy.
Originaly posted on kerastase-usa.com
Mila1222
41.756228509E12 26/08/2025
Didn't see any changes
It didn't work the way I expected. Smells great tho.
Originaly posted on kerastase-usa.com
Yamilca
51.755781224E12 21/08/2025
Serums
Love how this serum smells and how my hair reacts when I use it ❤️
Originaly posted on kerastase-usa.com
Josmar
51.764736381E12 02/12/2025
Me encanta
Me encanta es lo máximo mi cuero cabelludo lo necesitaba
Originaly posted on kerastase-usa.com
Lastar
41.7553567E12 16/08/2025
Good to have
This a good all purpose after shampoo and blow dry. It works nice and smells good. Because of the price I limit using to once or twice a week. I massage it in my scalp and through my hair. Smells good too.
Originaly posted on kerastase.ca
Castelia
51.755279907E12 15/08/2025
LOVED IT
[This review was collected as part of a promotion.] I live in Florida and the climate is not the best when you have curly hair and want them straight 24/7, but the Kerastase hair and scalp serum has been a lifesaver. It smells amazing, like milk, and even after I straighten my hair I can still smell it days after. It’s helped with new baby hairs and protects the hair I already have. It makes them smoother and silk like when i blow dry and straighten them .
Originaly posted on kerastase-usa.com
Nat Savage
51.76636341E12 21/12/2025
Easy to apply
[This review was collected as part of a promotion.] I got this product along with the shampoo and conditioner to help my hair grow longer, I’ve applied it twice now to my scalp , it’s not sticky on your hair or anything so you can’t tell when styling like some products and it smells good!
Originaly posted on kerastase-usa.com
Teddyd
51.753900206E12 30/07/2025
Good stuff
Works great my hair has grown inches in little time
Originaly posted on kerastase-usa.com
Imogen
31.753286171E12 23/07/2025
Not bad, a nice product overall
[This review was collected as part of a promotion.] This product is nice, it smells very clean and fresh. On the strands, it provides bit of a feeling of hydration and nourishment but I wouldn’t say that the result is anything life changing. For the cost of this product, you could get something else from this company that is much more effective. I’m not sure why they don’t improve this formula.
Originaly posted on kerastase-usa.com
Reply from Consumer Care Center 23/07/2025
Hi Imogen, thanks for reaching out about Résistance Extentioniste Scalp & Hair Serum. We are happy to hear you enjoyed the scent but we are sorry to hear this is not your new favorite product. Your feedback is important to us and we will be sure to share it with our team.
Rajae
51.752592517E12 15/07/2025
Holy grail
I got this because i noticed my hair was falling from the root and i could see hair follicels everytime i brush or a hair falLs. I paired this product with the "Initialiste Advanced scalp and hair serum" and in few days i have saw a difference. My hair is not shedding and it smells amazing.
The only problem is the applicatior it doesn't work well
Originaly posted on kerastase.ca
MF3333
31.760717672E12 17/10/2025
I don’t know if it made my hair grow faster
I used this for months and I honestly can’t say if it made it grow faster or not. I have stopped using it so we will see if my hair growth slows. But it did not make my hair greasy at all.
Originaly posted on kerastase-usa.com
Reply from Consumer Care Center 11/07/2025
Hi there, Thanks for your feedback on Résistance Extentioniste Scalp and Hair Serum. It's wonderful to hear that the serum did not leave your hair feeling greasy, which is a key benefit we strive for with our formulations. We're sorry to hear you're not seeing immediate results with the serum. We'll be sure to pass along your feedback to our team.
Growthserum giving result
51.760583812E12 15/10/2025
Seeing results.
I do see results in my growth. My hairdresser even commented on how rapid this product has affected my need to do color.
Originaly posted on kerastase-usa.com
TillysMom
51.760717681E12 17/10/2025
Great product
Great product, feels nice on my scalp. I only startied using so I have not seen results.
Originaly posted on kerastase-usa.com
CathyP
51.75102921E12 27/06/2025
Great for her growth
My hairstyle is recommended this product because of hair loss on the side of my head. I have been using it now for several months and I do see growth of new hair where it was known before. I highly recommend and will continue to use this product.
Originaly posted on kerastase-usa.com
Jennifer Can
51.750965306E12 26/06/2025
A game changer for Hair!
Love the “extentioniste line, the serum, the shampoo, conditioner & masque, all of them. I have thin blonde over processed hair and started using these products a month ago, my hair dresser suggested. In one month my hair is growing and so much healthier. My friends & family noticing my hair was longer and healthier asked what I am doing? They just ordered Kerastase too! Love Kérastase, it’s expensive but so worth it! 💛
Originaly posted on kerastase-usa.com
siena43
51.750977192E12 26/06/2025
Good serum, like that it works for scalp and hair
I thought that the serum does a good job moisturizing and sealing the ends of the hair, even more than other products in the line. I would reccomend. Not as good as genesis on the scalp, but think it also does a different function.
Originaly posted on kerastase-usa.com
Elizabeth B
51.767194373E12 31/12/2025
Love this serum
I have purchased about 5 bottles of this serum already which shows how much I love it. I have natural, 4B hair and this serum helps me so much with detangling. I know it's not really advertised as being a detangler but it is great. I use it on my scalp and lengths. I typically use it on dry hair. The smell is amazing.
Originaly posted on kerastase-usa.com
K Little
51.749843907E12 13/06/2025
It works
I have used this product for several years and have proven results. I apply after I wash my hair in a concentrated area
Originaly posted on kerastase-usa.com
Sexsmith
51.750205708E12 17/06/2025
My go-to hair serum
[This review was collected as part of a promotion.] My hair is fine, thin and blonde. Needless to say, breakage is a HUGE concern of mine. This serum works WONDERS and has made my hair grow longer and stronger than ever before!
Originaly posted on kerastase-usa.com
Riften
51.760717729E12 17/10/2025
Smells and feels great
I really like this hair and scalp serum. The smell is fantastic, like I just left the salon. It does not make my roots oily at all and I am prone to oily roots. I haven’t noticed if my hair growth has increased at all yet but it’s still new to me so hopefully with some time.
Originaly posted on kerastase-usa.com
Sofi909
51.749153609E12 05/06/2025
Maximum serum
Es el mejor serum tengo nuevos cabellos creciéndome si quieres que te crezca el cabello este es el mejor
Originaly posted on kerastase-usa.com
Paneltrix
51.749058208E12 04/06/2025
RainaM
31.749129183E12 05/06/2025
Its okay
Honestly, I really don't know if this is working or not. I have straight hair down to my chest and no scalp problems, just would like longer hair. This made my roots pretty oily and also is time consuming doing it the correct way they show in videos. I also use a lot more than 2 droppers worth.
Originaly posted on kerastase-usa.com
Reply from Consumer Care Center 05/06/2025
Hi RainaM, thank you for sharing your feedback on our Résistance Extentioniste Scalp & Hair Serum. We are sorry to hear that you have not noticed any results. We hope that with continued use, you will see an improvement in your hair. This product works on all hair types. We appreciate the time you took to share your review, and we will be passing your comments along to others on our team.
Asanga63
51.748409307E12 28/05/2025
Great serum
This serum smell divine and hoping it will help with my falling hair. I didn’t see much results yet but hoping it will. It is little oily if you add more. Perfect amount application does help.
Originaly posted on kerastase-usa.com
Adrienne A
51.748349926E12 27/05/2025
This stuff WORKS!
[This review was collected as part of a promotion.] This product was recommended by my stylist, and I've been using it for over a year now. In that time, I obtained a new stylist, and she cannot stop commenting on how much new growth I have! We can both tell how much thicker my hair is at the scalp, and now we just wait for it to grow the full length. I'm very happy!
Originaly posted on kerastase-usa.com
Haya01
51.748157306E12 25/05/2025
Great product
[This review was collected as part of a promotion.] I've been using this product forthe past 2 years. Since I used this product my hair is stronger and healthier, it is even growing longer. Easy to use, does not feel heavy or sticky. I will highly recomend it.
Originaly posted on kerastase-usa.com
Betchay
41.748718139E12 31/05/2025
Okay
[This review was collected as part of a promotion.] Smells good but no significant results from the advertised outcome.
Originaly posted on kerastase-usa.com
akwr27
41.756061111E12 24/08/2025
No results yet, but pleasant use
I'm only a month in so it's really hard to tell with these things, no obvious results yet, but it smells nice, is a nice texture and can't hurt. I'll have to report back if I see something fabulous happening, but overall I enjoy doing a scalp massage with it or throwing it on under my hat before baseball games.
Originaly posted on kerastase-usa.com
PaolaR
51.761011623E12 20/10/2025
The only hair serum that works!!
[This review was collected as part of a promotion.] I have used many other serums for hair growth and none of them has worked!! BUT THIS ONE, IS ABSOLUTELY THE BEST!! Even my friends noticed the difference between my hair after I used it. JUST USE IT! You will never regret it!!
Originaly posted on kerastase-usa.com
MAKEUPBYCLAUDITA
51.747199707E12 14/05/2025
Hair growth
Does work, takes a while to grow but it does the job
Originaly posted on kerastase-usa.com
Dynomite
51.746474309E12 05/05/2025
Great for hair growth
This is the best for hair growth. Wonderful product
Originaly posted on kerastase-usa.com
Ellisar
31.746557573E12 06/05/2025
Unclear result
[This review was collected as part of a promotion.] Have not see a huge change in my scalp and hair health. But scalp does feel clean after using it
Originaly posted on kerastase-usa.com
Reply from Consumer Care Center 06/05/2025
Hi there, Thanks for your feedback on Résistance Extentioniste Scalp & Hair Serum. We understand that while your scalp feels clean after using it, you haven't noticed significant changes in your scalp and hair health yet. Consistency is key with this serum, and results often become more noticeable with continued use over time. We encourage you to keep using the serum as directed and monitor its effects. If you have any specific concerns or questions, or if you'd like personalized advice, please don't hesitate to reach back out.
Aurora13
51.745857809E12 28/04/2025
Love this serum!
Leaves my hair feeling lightweight, shiny, and healthy!
Originaly posted on kerastase-usa.com
Agatha
51.745849118E12 28/04/2025
Great product
First time using this product, very silky and smooth.
Originaly posted on kerastase.ca
Elvistattoos
51.745287205E12 21/04/2025
Loving this line
Perfect for my thin fine longish hair. It feels like a great hair day every single time I use it .
Originaly posted on kerastase-usa.com
SayerK
41.772682982E12 04/03/2026
Works but be patience it is not magic
As you can see, the before picture was Jan 23 and the second April 20. The growing is there, I have been using the whole extensionise line since December, but the serum only since the beginning of February. I like it so far my hair is healthy and I can see the grow. I don't give or 5 stars because the serum price is too high for 50ml, it is the same price for the genesis serum which is 90 ml.
Originaly posted on kerastase-usa.com
Kitchenbeck
31.744912481E12 17/04/2025
Poor bottle choice
The glass tip you use to pull out the liquid is awful. The product is way to liquid that it just falls out, dripping everywhere..i was trying my best to be careful not to waste any..but recently a drop fell right in my eye. So im annoyed enough to come write a review. I also dont have sensative skin but i do feel some irritation. I wanted so bad for this to be all the hype, im only 1/3 in so i cant say if the product actually works yet.
Originaly posted on kerastase.ca
Reply from Vichy- CCC BEC 17/04/2025
Thank you for reaching out to Kerastase and sharing some feedback with us. We are so sorry to hear you had this kind of reaction to our Résistance Serum Extentioniste Scalp & Hair Serum. Although we make every effort to provide products of the finest quality, we recognize that there are occasions when someone may find a particular item is not compatible with their skin. Please discontinue use immediately. We would love to speak to you regarding your experience. We will be sending you an email to gather additional information about your experience and will be in touch once we receive your response.
Judy T
51.744299011E12 10/04/2025
Hair Growth
[This review was collected as part of a promotion.] This is great for someone who wants their hair to grow. Easy to use
Originaly posted on kerastase-usa.com
jenniet817
51.750111853E12 16/06/2025
Best stuff ever!
This is amazing, it does not make my hair greasy at all. Instead of just makes it feel and look healthier
Originaly posted on kerastase-usa.com
Dr Tuttle
51.75011186E12 16/06/2025
Best serum for thinning hair
Best serum for scalp health to support hair growth.
Originaly posted on kerastase-usa.com
La negra
51.743813026E12 04/04/2025
Love the smell, it doesn’t run and it smells great
I love how light weight this serum is! Great product
Originaly posted on kerastase-usa.com
Jojola
51.746179112E12 02/05/2025
The best serum for the scalp
Make my hair long stronger and is not oily! Smell good
Originaly posted on kerastase-usa.com
Heidy A
51.743422414E12 31/03/2025
Excelente
[This review was collected as part of a promotion.] Good product, it does its job, my hair is healthier
Originaly posted on kerastase-usa.com
Serum Extentioniste Scalp & Hair Serum 50ml
Kerastase - Résistance
A highly concentrated serum to help strengthen and fortify hair for reduced breakage.
Its non-greasy formula helps to protect the appearance of the scalp from environmental aggressors.
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