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Klorane

Intense Strengthening Serum with Quinine

Scalp treatment

  • Scalp treatment
  • Sulfate-free
  • Silicone-free
  • Protein-free
Size3.3 fl. oz.
Price$27.63seen at one store · 3.38 oz
Price / oz$10.15/ozat 3.38 oz

Add it to your products. We’ll tell you if it’s ever recalled.

Scent:

The ingredient list declares fragrance. What it smells of is not stated, and we do not guess.

Personal fit

Is this right for you?

Complete the consultation to see how well this product fits your hair and your goals. With 6,000+ products in our library, we can match you to the right ones.

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  • Every product matched against your hair across the 19 factors we check.
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  • Find products that do the same job at a lower cost.
  • Your goals, scalp, damage history, water, budget, and scent preferences all shape your plan.

$49 with 60 days of follow-up questions and plan updates

$99 with 12 months. Pay once; the year renews only if you choose.

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Upper-mid price for a scalp treatment

$10.15/oz at 3.38 oz, more than 56% of the 280 scalp treatments , which mostly run $3.84–19.05/oz. The cost less.

Price and stores

Great for

Protein-sensitive hairthat stiffens when protein is added
Fine hairthat flattens under most products
Silicone-free routinesno silicones appear in the list
Short ingredient listsfifteen ingredients or fewer

Maybe skip if

this product has a scent
Very dry or damaged hairit contains fast-drying alcohol
Dry or very humid airwhere heavy humectants work against you
Tight budgetsit sits in the upper price tiers
Picking it up locallywe’ve only seen it sold in one channel

Whether this much richness suits you depends on your strand thickness, porosity and how easily your hair goes flat. We work that out in the consultation.

What the formula actually does

Read from the label, not the marketing

Each row says where it comes from: F means we derived it from this product’s own ingredient list, S means it is a claim the brand makes that the formula neither confirms nor contradicts.

Slip and detangling Little

Nothing here is built to reduce combing force.

Oils and butters None

No oils or butters in the list.

Weight on the hair Light

Water-first and light: unlikely to flatten fine hair.

Water-binding (humectants) High

Humectants near the top: binding water is one of its main jobs.

Protein None

No protein or amino acids in the list.

Needs detergent to remove No

Nothing here needs a detergent wash to remove.

Hard-water defence None

No chelating agent in the list.

Fragrance Present

Fragrance is listed; it sits below the working ingredients.

from the formula stated by the brand reported by reviewers Scale: 1 dot low · 5 dots high, within this product type.

Ingredients that matter

The ingredients that change a decision

The workhorse ingredients, plus anything lower down that changes a decision. The chips name what an ingredient does. They are not safety scores, and no ingredient here is rated good or bad on its own.

IngredientWhat it doesWhy it mattersChip
WaterWater (aqua) solvent The base everything else is dissolved in Neutral
Alcohol Denat.Alcohol denat drying alcohol Speeds drying but can leave hair feeling dry Drying
Glycerin humectant Pulls water into the hair Moisturizes
Oleth-10 emulsifier Keeps oil and water mixed Stabilizes
Alcohol Denat.Alcohol drying alcohol Speeds drying but can leave hair feeling dry Drying
Biotin vitamin A marketed vitamin addition Neutral
Caffeine active The over-the-counter active Active
Cinchona Succirubra Bark Extract botanical extract A plant extract, there as much for marketing as for function Neutral
FragranceFragance (parfum) fragrance The scent Fragrance
What the list leaves out, and what it carriesThe list carries no sulfates or silicones. No protein: a moisture formula, not a repair one. Fragrance is on the label. Contains fast-drying alcohol.
Full ingredient list (13)

In the US, ingredients above 1% are listed from most to least. Below 1% they can appear in any order. Each note keeps three things apart: what the ingredient generally does, its role in this type of product, and what its position can tell you.

  • 1 Water · Water (aqua)
    General function

    The base of almost every rinse-off and cream hair product. It carries everything else and is normally the first ingredient on the label.

    Leading ingredient

    Listed in the first three ingredients, it is likely a structural part of this formula.

    • solvent
  • 2 Alcohol Denat. · Alcohol denat
    General function

    Fast-drying alcohol used to make sprays set quickly. In leave-on products it can leave hair feeling dry, especially in high position on the list.

    Leading ingredient

    Listed in the first three ingredients, it is likely a structural part of this formula.

    May suitFine or easily flattened hair

    Evaporates on contact, which is how a spray sets almost instantly and leaves no weight behind it.

    May not suitDry, coarse, or high-porosity hair

    Porous hair gives water up easily as it is; a fast-evaporating solvent high on the list accelerates that.

    May not suitVery dry or highly damaged hair

    It evaporates quickly and takes some water with it. On hair already short of moisture, a formula built on a lot of it can finish drier than it started.

    PubChem
    • drying alcohol
    • solvent
  • 3 Glycerin
    General function

    Glycerin, also called glycerol, attracts moisture and mixes completely with water.

    Leading ingredient

    Listed in the first three ingredients, it is likely a structural part of this formula.

    May suitDry, coarse, or high-porosity hair

    High-porosity hair loses water fast; a humectant holds some of it in place for longer than the wash itself would.

    May suitVery dry or highly damaged hair

    Binds water into the outer layers of the strand, and water is what makes dry hair flexible again rather than brittle.

    DependsClimate-sensitive or frizz-prone hair

    Water moves both ways. Measured across concentrations, glycerin solutions give water up in some conditions and take it from the air in others. What it does for you depends on how much of it is there and on the air around it.

    Scientific Reports
    • humectant
  • 4 Oleth-10
    General function

    An emulsifier used to disperse oils and fragrance.

    Supporting ingredient

    Listed in positions 4–8, it likely makes a meaningful contribution alongside the formula's main ingredients.

    • emulsifier
    • solubilizer
  • 5 Alcohol Denat. · Alcohol
    General function

    Fast-drying alcohol used to make sprays set quickly. In leave-on products it can leave hair feeling dry, especially in high position on the list.

    Supporting ingredient

    Listed in positions 4–8, it likely makes a meaningful contribution alongside the formula's main ingredients.

    May suitFine or easily flattened hair

    Evaporates on contact, which is how a spray sets almost instantly and leaves no weight behind it.

    May not suitDry, coarse, or high-porosity hair

    Porous hair gives water up easily as it is; a fast-evaporating solvent high on the list accelerates that.

    May not suitVery dry or highly damaged hair

    It evaporates quickly and takes some water with it. On hair already short of moisture, a formula built on a lot of it can finish drier than it started.

    PubChem
    • drying alcohol
    • solvent
  • 6 Biotin
    General function

    Vitamin B7, included for label appeal in thickening and growth-positioned products. Applied to hair it does not reach the follicle.

    Supporting ingredient

    Listed in positions 4–8, it likely makes a meaningful contribution alongside the formula's main ingredients.

    PubChem
    • vitamin
  • 7 Caffeine
    General function

    Included in scalp and thickening products for label appeal. Evidence for applied caffeine changing hair growth is limited.

    Supporting ingredient

    Listed in positions 4–8, it likely makes a meaningful contribution alongside the formula's main ingredients.

    PubChem
    • active
  • 8 Cinchona Succirubra Bark Extract
    General function

    An extract from the bark of Cinchona Succirubra. Plant extracts are used across a wide range of levels, and label order is the best guide to how much is here.

    Supporting ingredient

    Listed in positions 4–8, it likely makes a meaningful contribution alongside the formula's main ingredients.

    • botanical extract
  • ▾Below about here, the order stops meaning much. These are usually used at 1% or less.
  • 9 Citric Acid
    General function

    Used to bring the product to a slightly acidic pH, which helps the cuticle lie flat. It is almost always near the end of the list.

    Estimated lower-concentration zone

    It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

    May suitBuild-up-sensitive routines

    Holds hard-water minerals in solution so they rinse away instead of depositing on the hair.

    May suitFrizz-prone, damaged, or high-friction hair

    The acid side of pH adjustment, and the reason it matters is measured: alkaline formulas raise the fibre's surface negative charge, increase friction between strands and lift the scales, while lower-pH ones do the reverse.

    May suitGray, silver, or brass-prone hair

    Where a warm cast comes from water minerals rather than from the hair itself, holding those metals in solution is what removes it.

    International Journal of Trichology
    • pH adjuster
    • hard-water chelator
  • 10 Fragrance · Fragance (parfum)
    General function

    An undisclosed blend of scent ingredients. Regulations let it stay unlisted, so a fragrance-free product is the only way to be certain what is not in it.

    Estimated lower-concentration zone

    It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

    May not suitFragrance-sensitive routines

    Declared fragrance. On a fragrance-sensitive routine this is the line that decides it, wherever it sits on the label.

    • fragrance
    • declared fragrance
  • 11 Myrciaria Dubia Fruit Extract
    • botanical extract
  • 12 Propanediol
    General function

    A corn-derived humectant and solvent, often chosen as a lighter-feeling alternative to propylene glycol.

    Estimated lower-concentration zone

    It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

    May suitFine or easily flattened hair

    Light and water-binding rather than oily, so it adds less weight than oils or butters do.

    May suitVery dry or highly damaged hair

    A small water-binding solvent. It holds moisture and helps the rest of the formula spread evenly over the strand.

    DependsClimate-sensitive or frizz-prone hair

    A humectant follows the air: it holds water in humid conditions and can give it up in very dry ones. Climate decides what it does more than the label does.

    PubChem
    • humectant
    • solvent
  • 13 Tocopherol
    • antioxidant
    • vitamin

What the whole list adds up to

  • 4 solvents
  • 2 drying alcohols
  • 2 humectants
  • 2 vitamins
  • 2 botanical extracts
  • 1 emulsifier
  • 1 solubilizer
  • 1 active
  • 1 pH adjuster
  • 1 hard-water chelator
  • 1 fragrance
  • 1 declared fragrance
  • 1 antioxidant

Ingredient list captured 2026-10-07. Formulas change, so check the package in your hand when an ingredient matters to you.

Price · 3.38 oz

Seen at $27.63 lowest of 2 stores · checked Oct 8
Good value under $12 Under $3.46/oz it costs less than three-quarters of the 8 products we score as doing the same job

Priced above the products that do the same job. Stores sell it above the $12 line; products that do this job typically go for about $22 at this size.

Show the price ladder
Where we’ve seen it3 listings · 3 stores

Sorted by price per ounce. Dated observations from our research, not live prices. Direct store pages, no affiliate links. We don’t sell this product. and 1 listing we don’t count, from grey-market or unverified sellers.

How we work this out
  1. 3.38 oz is the size stores list most often; every comparison on this page is made at it. Other sizes are shown in the Sizes row and the store list.
  2. Seen at $27.63 is the price we have observed for the 3.38 oz. We need three stores before we call a price commonly seen.
  3. Good value under $12 comes from the 8 products we score as doing the same job as this one. A quarter of them cost less than $3.46/oz; at 3.38 oz that is $12. Under that line you are paying less than most of them.
  4. About $22 is what those same products typically cost at this size: the midpoint of their prices per ounce, scaled to 3.38 oz.

Formula

Formula score
3 of 10

Mid-range per ounce for a shorter formula: there is no conditioning agents up front here.

How the score is counted
  • 5 products that do the same job cost less per ounce
  • Costs more per ounce than 56% of the 280 scalp treatments we’ve priced
  • No conditioning agents up front in the formula
  • No oils or butters in the working zone either
  • Conditioning agents up frontWhat makes wet hair comb through.3 pts
  • Oils or butters in the working zoneSoftens the strand rather than just coating it.2 pts
  • Slip for detanglingReduces the force it takes to comb wet hair.2 pts
  • A humectantBinds water into the hair.1 pt
  • A pH adjusterBrings the formula to the acidic pH hair prefers.1 pt
  • Fragrance kept out of the top eightScent as a finishing touch, not a major share.1 pt

The formula score measures completeness for the job: a weighted share of the systems this product type is usually built around that we find in this list. It does not rate how well the product works or its quality, and it never compares across product types.

Does the same job, for less

Formulas that do the same things (cleanse, condition, coat or hold) for less per ounce. Scent, texture and where you buy them can still differ.

MizaniLowest cost per oz Scalp Care Soothing Serum $2.83/oz $7.32/oz less
  • Fragrance-free
  • Protein-free
  • Lightweight
· Same function
Differs
  • Masstige tier
  • 4 oz bottle
Compare
Bella HueSame function Rosemary Scalp Scrub $3.67/oz $6.48/oz less
  • Fragrance-free
  • Protein-free
  • Lightweight
Differs
  • Mint scent
  • 9 oz bottle
Compare
Marc AnthonySame function Hair & Scalp Detox Purifying Scalp Scrub with Mineral Salt $7.24/oz $2.91/oz less
  • Protein-free
  • Lightweight
  • Silicone-free
Differs
  • Mint scent
  • Cruelty-free
  • Masstige tier
Compare

See more alternatives in the product library

These products do a similar job. We haven’t matched them to you. Find the one that fits your hair, routine and budget

Suits every hair pattern

Final decision

Should you buy it?

Good for the right person
Best user

Hair that stiffens on protein, for a protein-free formula and something that will not weigh hair down

Biggest tradeoff

Worth skipping for anyone sensitive to fragrance, very dry or high-damage hair, or very dry or very humid climates

We do not sell products or take placement fees. This page states what the formula and the prices show; the consultation is what matches it to a person.

More from Klorane

How this page was made

  • Everything above comes from our researched product record: identity, the ingredient list as printed, the brand's own claims, dated prices and review themes our researchers wrote in their own words. No part of this page is written by hand for one product.
  • The value band is a fixed label over two stored numbers: this product’s cost per ounce as a percentile of every product of this type we have priced, each at the size it is most often sold in, and how many products we score as doing the same job cost at least a quarter less per ounce.
  • Both scores out of ten are defined on this page. The formula score is completeness for the job, computed from a fixed per-format checklist shown beneath the gauge; the price score is cost per ounce against every product of this type we have priced.
  • The "Is this right for you?" panel reads only your own consultation answers, and it applies exactly the filters our recommendation engine applies. It is computed when you load the page and is never stored on it.
  • 2 sources consulted for this product (1 manufacturer or regulatory, 0 retailer, 1 editorial), last checked 2026-10-07.
  • Ingredient references are linked for 5 of 6 product-aware annotations on this page. Fit notes are general formulation guidance. They aren’t a verdict on the finished product or on you.
  • We haven’t tested this product in a lab, and we don’t physically test your hair. Formula readings come from the ingredient list. Claims about how it behaves are labelled as the brand's.
  • Ingredient order tells you relative amount only above roughly 1%. Prices are what we saw on the dates shown and can change.
  • Ingredient names link to our ingredient library, where each entry shows what it does, which product types use it, and where it usually sits on a label across everything we have researched.
  • This is cosmetic information, not medical advice, and nothing here diagnoses or treats a health condition.
  • Formula readings: derivation v23. Record last updated 2026-10-08.

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