K18 Peptide Prep pH Maintenance Shampoo: a Guru Score of 86%

What the gurus are saying.

Every take we've logged from this product's reviews across YouTube. Click any row to watch the moment they said it.

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✓Yay

"I absolutely love and splurge on all the time. It's a great gentle detoxifying shampoo with the K18 trademark peptide that really helps to remove buildup, that really helps to clarify your scalp and your hair and prep your hair for the K18 treatment, but at the same time doesn't make your hair feel really stripped or dry. It removes up to 99% of product buildup, 95% of seabum buildup and the other kind of hard minerals that you may get from the water or pollution."

Top Pick: clarifying shampoo

All 6 takes from Dr. Jenny Liu

Budget Haircare That Performs Like Luxury | Dermatologist Dr. Jenny Liu

"I absolutely love and splurge on all the time. It's a great gentle detoxifying shampoo with the K18 trademark peptide that really helps to remove buildup, that really helps to clarify your scalp and your hair and prep your hair for the K18 treatment, but at the same time doesn't make your hair feel really stripped or dry. It removes up to 99% of product buildup, 95% of seabum buildup and the other kind of hard minerals that you may get from the water or pollution."

Dermatologist Favorite Haircare Products of 2024 | Dr. Jenny Liu

"I really love [...] this shampoo right before I use the K18 Bond repair treatment to really set my hair and scalp up for that. [...] Ingredient wise it's got activated charcoal to absorb the sebum buildup and other residues, metals from the water, etc."

Hair Cycling Routine according to a dermatologist | Dr. Jenny Liu

"I find that of all the clarifying shampoos I've used, this is the one that feels the best on my hair afterwards. After I rinse it out, often clarifying shampoos [...] because they're so effective at cleansing, it makes my hair feel a little bit dry and crunchy after rinsing it out, but this K18 detox shampoo does not do that. It is very gentle and contains the K18 peptide that is in their bond repair that helps to reinforce hair strength and reduce breakage."

Dermatologist's Favorite Sephora Skincare & Haircare Products | Dr. Jenny Liu

"If you're looking for a good clarifying shampoo that gets a job done while minimizing dryness to the hair, you've got to check out K18. Their detox shampoo, I am obsessed with it and I have to say probably is by far to date my favorite clarifying shampoo. This shampoo first of all is safe to use on color treated hair."

Sephora Spring Savings Event 2024 | Dr. Jenny Liu

"K18 their detox shampoo is a lovely great clarifying shampoo to use once a week especially to prep your hair for the K18 treatment mask if you use that, but it's just really nice at removing all the buildup, the sebum, the debris, whatever products or dry shampoo that you may use on your scalp."

Dermatologist updated Haircare routine | Dr. Jenny Liu

"One of my favorite clarifying shampoos that I absolutely love is from K18, their detox shampoo. I absolutely love this shampoo because it's very gentle on all fronts but works really well. Clarifying shampoos usually have stronger detergents to just remove everything, and with that I worry about what it does to my hair, if it makes my hair feel more brittle and dry, but this one does not. At the same time, afterwards my scalp also feels very refreshed."

Tea with MD

115k subs

✓Yay

"The K18 Peptide Prep Detox Shampoo really delivers that deep clean without stripping your scalp skin barrier, and it does help prep your hair for treatments, for heat styling or if you're going in for hair dyeing or for curling or things like that. It contains activated charcoal which helps to draw out dirt, oil and impurities. It also has salicylic acid which helps to gently exfoliate your scalp, lift off those dead flakes. Salicylic acid is a great ingredient actually for dandruff."

Alexandra Anele

1.45M subs

✓Yay

"I really like it. It really gets down to the scalp and I feel like it fluffs everything up. So if you are someone who uses a lot of product and you tend to get buildup, using a clarifying shampoo occasionally, so good. So good. Or even if you're just someone who has an oily scalp, you know, your hair is fine, you have an oily scalp, using a clarifying shampoo occasionally, it just makes such a difference. You'll notice so much more volume in your hair. And I've really been liking this one."

Sincerely Miss Ash

195k subs

✓Yay

"This is one of the best from the drugstore. I really like this shampoo, it does a really good job to cleanse without stripping your hair. Your hair doesn't feel like straw, it's not all matted when you hop out of the shower. It does a really good job and I also find that it gives that nice shine to the hair as well. This is the one that you can use pretty much every single day."

Top Pick: clarifying shampoo

All 4 takes from Sincerely Miss Ash

BEAUTY PRODUCT'S I'VE USED UP || BEAUTY EMPTIES 2024 - SINCERELY MISS ASH

"I have an empty K18 Peptide Prep, this is the pH maintenance shampoo you can use this every hair wash. This one will give your hair a little bit of shine, it never weighs down my hair either and it does give that nice bounce to my hair as well. I really like this one and it never ever disappoints. It doesn't strip my hair of all of its moisture, it keeps the moisture in the hair and your hair still looks and feels incredible. Yes, I did purchase another one."

BEAUTY EMPTIES 2025 || SKINCARE, MAKEUP AND HAIRCARE PRODUCT'S I'VE USED UP - PROJECT PAN

"This is one of the best from the drugstore. I really like this shampoo, it does a really good job to cleanse without stripping your hair. Your hair doesn't feel like straw, it's not all matted when you hop out of the shower. It does a really good job and I also find that it gives that nice shine to the hair as well. This is the one that you can use pretty much every single day."

SEPHORA VIB SALE RECOMMENDATIONS & TOP PICKS | HOLIDAY EVENT 2023 PART:1

"This is literally the best that I've ever used. I won't use anything else. This really has made the biggest difference on my hair. I actually look forward to clarifying my hair because it's the one clarifying shampoo that actually keeps my hair feeling like my hair. It doesn't feel dry, it doesn't get all tangly, it's truly amazing. If you're looking for a good detox shampoo, I would say pick this up. I use this pretty much once a month, sometimes twice a month."

SEPHORA VIB SALE RECOMMENDATIONS | SPRING SAVINGS EVENT 2024 - SKINCARE, MAKEUP & HAIRCARE

"This is literally the best clarifying shampoo I have ever used. I have used many different clarifying shampoos in the past and [...] they have all made my hair look and feel like straw and I hate that feeling. I really hate when my hair looks and feels crunchy because the clarifying shampoo just literally stripped all of the goodness out of my hair."

Dr. Sam Ellis

898k subs

✓Yay

"Probably the two I use the most in my shower are the one by K18 and the one by Whey, both work really well. A little bit goes a long way, they lather really nicely so it feels good as a cleanser, and I just find that my hair looks great afterward too."

All 2 takes from Dr. Sam Ellis

How To Grow Longer, Healthier Hair Fast | Hair and Scalp Tips | Dr. Sam Ellis

"One of my favorites that I have tried is by K18. I find that their Peptide Prep pH Maintenance Shampoo strikes a really nice balance of making my scalp and hair feel really clean but not dried out. I will often use this K18 clarifying shampoo in conjunction with that buildup detox spray and I do that about once a week where I'm going to do the spray first, let it sit at least 15 minutes, and then go into the shower and use my clarifying shampoo."

Dermatologist's Healthy Haircare Upgrades for 2025 | Dr. Sam Ellis

"Probably the two I use the most in my shower are the one by K18 and the one by Whey, both work really well. A little bit goes a long way, they lather really nicely so it feels good as a cleanser, and I just find that my hair looks great afterward too."

Beyond50Skin

32k subs

✓Yay

"This is the K18 Peptide Prep. Now this is not a cheap product, but it's actually one of the few clarifying shampoos they call it a detox shampoo that just kind of gets rid of all that buildup on your scalp and on your hair from all the products that you use throughout the week. Now I use this every other week. It took me forever to get through it. The only complaint I have is it turned into kind of this gel-like stuff toward the end of its use."

All 2 takes from Beyond50Skin

Beauty Favorites & Fails: What Worked & What Didn't for My Sensitive Over 50 Skin!

"This is the K18 Peptide Prep. Now this is not a cheap product, but it's actually one of the few clarifying shampoos they call it a detox shampoo that just kind of gets rid of all that buildup on your scalp and on your hair from all the products that you use throughout the week. Now I use this every other week. It took me forever to get through it. The only complaint I have is it turned into kind of this gel-like stuff toward the end of its use."

Best Beauty of 2023! Every Category SUBSCRIBERS I HAVE EXCITING NEWS🎉

"I hadn't used a detox shampoo in many years, and I really like the Peptide Prep by K18. I use it once a month, once every other month, just to get rid of all that buildup."

Robert Welsh

1.11M subs

✓Yay

"I use K18."

James Welsh

1.58M subs

✓Yay

"This is K18 Peptide Prep Detox Shampoo. I love my Head & Shoulders, but this has converted me, I'll be honest. They say that this is a color safe, clarifying shampoo with skincare inspired ingredients, plus micro dosed with the K18 peptide to nourish hair while removing buildup for clean, healthy hair canvas. It has a non-stripping lather which helps to unclog hair follicles while banishing dirt, oils, silicones and things left behind from heavy product buildup."

HotandFlashy

1.23M subs

✓Nay

"Then I was like well no wonder with these ingredients like this has very high SD alcohol so that is going to dry out my hair and sure enough it did. And this one has the ingredient that I really don't like which is that sodium C1416 olefin sulfonate my hair does not like that that just dries my hair out like crazy."

What the evidence says.

Independent of what the gurus think, this is what the published research supports about the main active ingredients here.

Salicylic acid

Salicylic acid dissolves in oil, so it can get into a pore rather than just working on the surface. That is why it has long-standing evidence for blackheads and milder acne.

Source: DermNet

Humectants and emollients

Ingredients like these draw water into the surface layers and slow how fast it leaves. The evidence is for comfort, softness and hydration rather than for changing the structure of the skin.

Source: DermNet

Peptides

Peptides are short protein fragments meant to signal repair. The evidence for them is thinner than for retinoids or vitamin C, and it varies a lot by the specific peptide, so the category is more promising than proven.

Source: NIH, National Library of Medicine

Frequently asked.

What is K18 Peptide Prep pH Maintenance Shampoo?

A clarifying shampoo with K18 peptides, activated charcoal and salicylic acid designed to remove product buildup and clarify hair and scalp without stripping moisture.

Is K18 Peptide Prep pH Maintenance Shampoo worth it?

Mostly yes. 8 of the 9 gurus who reviewed it give it their stamp of approval, for a Guru Score of 86%.

What is K18 Peptide Prep pH Maintenance Shampoo's Guru Score?

K18 Peptide Prep pH Maintenance Shampoo holds a Guru Score of 86%. That is our read on how warmly the experts talk about it, based on the verdicts of 9 expert reviewers we have collected. It is also Guru Certified, our mark for products that hold broad approval across many expert reviewers.