Follow us on our new Insta page »
Redken Scalp Relief Dandruff Control Shampoo

Scalp Relief Dandruff Control Shampoo

Dandruff control shampoo with pyrithione zinc gently cleanses hair while helping to eliminate and control flaking and irritation caused by dandruff.
Uploaded by: sofiethebee on

Redken Scalp Relief Dandruff Control Shampoo
Ingredients explained

Also-called: Aqua | What-it-does: solvent

Good old water, aka H2O. The most common skincare ingredient of all. You can usually find it right in the very first spot of the ingredient list, meaning it’s the biggest thing out of all the stuff that makes up the product. 

It’s mainly a solvent for ingredients that do not like to dissolve in oils but rather in water. 

Once inside the skin, it hydrates, but not from the outside - putting pure water on the skin (hello long baths!) is drying. 

One more thing: the water used in cosmetics is purified and deionized (it means that almost all of the mineral ions inside it is removed). Like this, the products can stay more stable over time. 

Also-called: SLES | What-it-does: surfactant/cleansing, emulsifying

It’s probably the most common cleansing ingredient of all. It’s usually the Chief Bubble Officer responsible for big bubbles in cleansing products through the foam it creates is a bit airy and loose and not as dense and luxurious as the foam created by infamous SLS

As for mildness, it goes somewhere in the middle. It’s often confused with sodium lauryl sulfate (SLS), but they are absolutely not the same. The SLES molecule has a bigger water-soluble head part that makes it milder and much less irritating. It is considered absolutely ok in the amount used in cosmetic products, though if you are looking for a mild facial cleanser, you have better chances with a formula without SLES. For an average shower gel? SLES works just fine.  

Also-called: SLS | What-it-does: surfactant/cleansing, emulsifying | Comedogenicity: 0

The famous or rather infamous SLS (not to be confused with SLES). It is a cleansing agent known for being too good at the job and potentially irritating the skin. But, on the positive side,  it can produce copious, creamy and luxurious foam compared to the more gentle and thus nowadays much more commonly used Sodium Laureth Sulfate.

In fact, SLS is so good at irritating the skin that it is very commonly used in dermatological studies just for that. It is a so-called "primary irritant", a substance that irritates the skin in one go (without prior sensitization) but doesn't do any other big harm (such as being carcinogenic or systematically toxic - those claims are not true). Also, the formula can greatly influence the irritating potential of SLS, and mixing it with other cleaning agents makes it milder

If it's not in a cleanser, it works as an emulsifier or even as a penetration enhancer for active materials. 

Glycerin - superstar
Also-called: Glycerol | What-it-does: skin-identical ingredient, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0
  • A natural moisturizer that’s also in our skin
  • A super common, safe, effective and cheap molecule used for more than 50 years
  • Not only a simple moisturizer but knows much more: keeps the skin lipids between our skin cells in a healthy (liquid crystal) state, protects against irritation, helps to restore barrier
  • Effective from as low as 3% with even more benefits at higher concentrations up to 20-40% (around 10% is a good usability-effectiveness sweet spot)
  • High-glycerin moisturizers are awesome for treating severely dry skin
Read all the geeky details about Glycerin here >>

A cleansing agent whose main thing is adding viscosity and foam to cleansing formulas

Chemically speaking, it is the little sister of Cocamide DEA and has similar properties to that guy. However, being a monoethanolamine instead of diethanolamine has the advantage that the nitrosamine-concern does not apply for Cocamide MEA.

A so-called diester created from two stearic acid molecules and an ethylene glycol molecule. Its main thing is being an opacifier and pearling agent in cleansing products making them white and glossy. It can also give body to creams and emulsions.

Also-called: Salt | What-it-does: viscosity controlling

Sodium chloride is the fancy name of salt. Normal, everyday table salt

If (similar to us) you are in the weird habit of reading the label on your shower gel while taking a shower, you might have noticed that sodium chloride is almost always on the ingredient list. The reason for this is that salt acts as a fantastic thickener in cleansing formulas created with ionic cleansing agents (aka surfactants) such as Sodium Laureth Sulfate. A couple of percents (typically 1-3%) turns a runny surfactant solution into a nice gel texture.

If you are into chemistry (if not, we understand, just skip this paragraph), the reason is that electrolytes (you know, the Na+ and Cl- ions) screen the electrostatic repulsion between the head groups of ionic surfactants and thus support the formation of long shaped micelles (instead of spherical ones) that entangle like spaghetti, and viola, a gel is formed. However, too much of it causes the phenomenon called "salting out", and the surfactant solution goes runny again. 

Other than that, salt also works as an emulsion stabilizer in water-in-oil emulsions, that is when water droplets are dispersed in the outer oil (or silicone) phase. And last but not least, when salt is right at the first spot of the ingredient list (and is not dissolved), the product is usually a body scrub where salt is the physical exfoliating agent

What-it-does: preservative

We don't have description for this ingredient yet.

What-it-does: solvent, emulsifying, perfuming, surfactant/cleansing | Irritancy: 0-1 | Comedogenicity: 0-2

Similar to other glycols, it's a helper ingredient used as a solvent, or to thin out thick formulas and make them more nicely spreadable. 

Hexylene Glycol is also part a preservative blend named Lexgard® HPO, where it helps the effectiveness of current IT-preservative, phenoxyethanol

What-it-does: emollient | Irritancy: 0 | Comedogenicity: 1

Probably the most common silicone of all. It is a polymer (created from repeating subunits) molecule and has different molecular weight and thus different viscosity versions from water-light to thick liquid.

As for skincare, it makes the skin silky smooth, creates a subtle gloss and forms a protective barrier (aka occlusive). Also, works well to fill in fine lines and wrinkles and give skin a plump look (of course that is only temporary, but still, it's nice). There are also scar treatment gels out there using dimethicone as their base ingredient. It helps to soften scars and increase their elasticity. 

As for hair care, it is a non-volatile silicone meaning that it stays on the hair rather than evaporates from it and smoothes the hair like no other thing. Depending on your hair type, it can be a bit difficult to wash out and might cause some build-up (btw, this is not true to all silicones, only the non-volatile types). 

What-it-does: buffering

Citric acid comes from citrus fruits and is an AHA. If these magic three letters don’t tell you anything, click here and read our detailed description on glycolic acid, the most famous AHA. 

So citric acid is an exfoliant, that can - just like other AHAs - gently lift off the dead skin cells of your skin and make it more smooth and fresh. 

There is also some research showing that citric acid with regular use (think three months and 20% concentration) can help sun-damaged skin, increase skin thickness and some nice hydrating things called glycosaminoglycans in the skin. 

But according to a comparative study done in 1995, citric acid has less skin improving magic properties than glycolic or lactic acid. Probably that’s why citric acid is usually not used as an exfoliant but more as a helper ingredient in small amounts to adjust the pH of a formulation. 

Parfum - icky
Also-called: Fragrance, Parfum;Parfum/Fragrance | What-it-does: perfuming

Exactly what it sounds: nice smelling stuff put into cosmetic products so that the end product also smells nice. Fragrance in the US and parfum in the EU is a generic term on the ingredient list that is made up of 30 to 50 chemicals on average (but it can have as much as 200 components!). 

If you are someone who likes to know what you put on your face then fragrance is not your best friend - there's no way to know what’s really in it.  

Also, if your skin is sensitive, fragrance is again not your best friend. It’s the number one cause of contact allergy to cosmetics. It’s definitely a smart thing to avoid with sensitive skin (and fragrance of any type - natural is just as allergic as synthetic, if not worse!). 

What-it-does: preservative

A helper ingredient that helps to make the products stay nice longer, aka preservative. It works mainly against fungi. 

It’s pH dependent and works best at acidic pH levels (3-5). It’s not strong enough to be used in itself so it’s always combined with something else, often with potassium sorbate.

Also-called: lye | What-it-does: buffering

The unfancy name for it is lye. It’s a solid white stuff that’s very alkaline and used in small amounts to adjust the pH of the product and make it just right. 

For example, in case of AHA or BHA exfoliants, the right pH is super-duper important, and pH adjusters like sodium hydroxide are needed.  

BTW, lye is not something new. It was already used by ancient Egyptians to help oil and fat magically turn into something else. Can you guess what? Yes, it’s soap. It still often shows up in the ingredient list of soaps and other cleansers.

Sodium hydroxide in itself is a potent skin irritant, but once it's reacted (as it is usually in skin care products, like exfoliants) it is totally harmless.

We don't have description for this ingredient yet.

What-it-does: viscosity controlling, emulsion stabilising | Irritancy: 0 | Comedogenicity: 1

A big molecule created from repeated subunits (a polymer of acrylic acid) that magically converts a liquid into a nice gel formula.  It usually has to be neutralized with a base (such as sodium hydroxide) for the thickening to occur and it creates viscous, clear gels that also feel nice and non-tacky on the skin. No wonder, it is a very popular and common ingredient. Typically used at 1% or less in most formulations.

What-it-does: viscosity controlling

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

Salicylic Acid - superstar
Also-called: BHA | What-it-does: exfoliant, anti-acne, soothing, preservative
  • It's one of the gold standard ingredients for treating problem skin
  • It can exfoliate skin both on the surface and in the pores
  • It's a potent anti-inflammatory agent
  • It's more effective for treating blackheads than acne
  • For acne combine it with antibacterial agents like benzoyl peroxide or azelaic acid
Read all the geeky details about Salicylic Acid here >>

What-it-does: moisturizer/humectant

We don't have description for this ingredient yet.

Eugenol - icky
What-it-does: perfuming

A colorless or yellowish oil that's used as a fragrance. It has a spicy scent and can be found for example in basil, clove or cinnamon oil.

A 2006 in-vitro  (made in the lab not on real people) study examined if clove oil is cytotoxic and found that not only clove oil but also its main constituent, eugenol is cytotoxic even at very low concentration (0.03%). It’s also one of the “EU 26 fragrances” that has to be labelled separately (and cannot be simply included in the term “fragrance/perfume” on the label) because of allergen potential. Best to avoid at least in leave-on products.

Limonene - icky
What-it-does: perfuming, solvent, deodorant

A super common and cheap fragrance ingredient. It's in many plants, e.g. rosemary, eucalyptus, lavender, lemongrass, peppermint and it's the main component (about 50-90%) of the peel oil of citrus fruits.

It does smell nice but the problem is that it oxidizes on air exposure and the resulting stuff is not good for the skin. Oxidized limonene can cause allergic contact dermatitis and counts as a frequent skin sensitizer

Limonene's nr1 function is definitely being a fragrance component, but there are several studies showing that it's also a penetration enhancer, mainly for oil-loving components.

All in all, limonene has some pros and cons, but - especially if your skin is sensitive - the cons probably outweigh the pros.  

Also-called: Carboxymethyl Cellulose | What-it-does: viscosity controlling, emulsion stabilising | Irritancy: 0 | Comedogenicity: 0

A cellulose (the big molecule found in the cell wall of green plants) derivative that is used as an emulsion stabilizer and thickener

Lecithin - goodie
What-it-does: emollient, emulsifying

A very common ingredient that can be found in all cell membranes. In cosmetics it's quite the multi-tasker: it's an emollient and water-binding ingredient but it's also an emulsifier and can be used for stabilization purposes. It's also often used to create liposomes

What-it-does: buffering

We don't have description for this ingredient yet.

What-it-does: buffering

We don't have description for this ingredient yet.

Also-called: Lavender Essential Oil | What-it-does: antimicrobial/antibacterial, perfuming

We have to start by writing how fascinated we are by the amazing lavender fields of Provance and we do love pretty much everything about lavender: its look, its color, its scent.... but, when it comes to skincare, lavender is a questionable ingredient that you probably do not want in your skincare products.

First, let us start with the pros: it has a lovely scent, so no wonder that it is popular as a fragrance ingredient in natural products wanting to be free from synthetic fragrances but still wanting to smell nice. The scent of lavender is famous for having calming and relaxing properties and some smallish scientific studies do support that. Inhaled volatile compounds seem to have a soothing effect on the central nervous system and studies have shown that lavender aromatherapy can improve patient's anxiety and experience in hospitals.   

Another pro is that lavender oil has some nice antimicrobial and antibacterial properties. It also has some local pain relieving and muscle relaxing magical powers. Lavender oil is also often claimed to have anti-inflammatory properties. We have found a study confirming this but it was the essential oil of the leaves and not the much more commonly used flowers and the two differ in their main chemical compounds very much. (The main components of the flower essential oil are linalyl acetate and linalool [around 80% the two together] while it is 1,8-Cineole [around 65%] in the essential oil of the leaves.)

Now, let us look at the cons: similar to a bunch of other essential oils, the main components of lavender oil are potentially irritating fragrant components. The two main components are linalyl acetate (about 50%) and linalool (about 35%) and both autoxidise on exposure to the air forming strong contact allergens. To make things even worse, lavender oil seems to be cytotoxic from concentrations as low as 0.25% (concentration up to 0.125% were ok). 

There is also an often cited Japanese study that made patch tests with lavender oil for 9 years and found a huge increase in lavender oil sensitivity in 1997 (from 1.1% in 1990 to 8.7% in 1997 and 13.9% in 1998). This was the year when using dried lavender flowers in pillows, wardrobes, and elsewhere became fashionable in Japan, so it seems that increased exposure to lavender results in increased risk of sensitivity.

Overall, it makes us sad to write bad things about such a lovely plant, but when it comes to skincare, you will be better off without lavender. 

What-it-does: preservative

As you may guess, if something is only recommended in products that you rinse off (cleansers and shampoos), then it’s probably not the best ingredient for the skin.

Methylisothiazolinone (MI) is a preservative that' super efficient against bacteria at surprisingly low concentrations. The problem with it though is that it can also sensitize and irritate the skin quite easily when it comes in leave-on formulas.

Currently, some countries are considering to ban it entirely (like Denmark) and the permitted use level is very low (under 0.01%). Luckily there are plenty of products on the market with other preservative options so if you are a better safe than sorry type it's probably best to avoid it. 

You may also want to take a look at...

what‑it‑does solvent
Normal (well kind of - it's purified and deionized) water. Usually the main solvent in cosmetic products. [more]
what‑it‑does surfactant/cleansing | emulsifying
It’s probably the most common cleansing ingredient of all. It’s usually the Chief Bubble Officer responsible for big bubbles in cleansing products through the foam it creates is a bit airy and loose and not as dense and luxurious as the foam created by infamous SLS.  As for mildness, it goes somewhere in the middle. [more]
what‑it‑does surfactant/cleansing | emulsifying
com. 0
The famous or rather infamous SLS (not to be confused with SLES). It is a cleansing agent known for being too good at the job and potentially irritating the skin. [more]
what‑it‑does skin-identical ingredient | moisturizer/humectant
irritancy, com. 0, 0
A real oldie but a goodie. Great natural moisturizer and skin-identical ingredient that plays an important role in skin hydration and general skin health. [more]
what‑it‑does surfactant/cleansing | viscosity controlling | emulsifying
A cleansing agent whose main thing is adding viscosity and foam to cleansing formulas.  Chemically speaking, it is the little sister of Cocamide DEA and has similar properties to that guy. [more]
what‑it‑does emollient | emulsifying | viscosity controlling
A so-called diester created from two stearic acid molecules and an ethylene glycol molecule. Its main thing is being an opacifier and pearling agent in cleansing products making them white and glossy. [more]
what‑it‑does viscosity controlling
Sodium chloride is the fancy name of salt. Normal, everyday table salt.  If (similar to us) you are in the weird habit of reading the label on your shower gel while taking a shower, you might have noticed that sodium chloride is almost always on the ingredient list. [more]
what‑it‑does preservative
what‑it‑does solvent | emulsifying | perfuming | surfactant/cleansing
irritancy, com. 0-1, 0-2
Similar to other glycols, it's a helper ingredient used as a solvent, or to thin out thick formulas and make them more nicely spreadable.  Hexylene Glycol is also part a preservative blend named Lexgard® [more]
what‑it‑does emollient
irritancy, com. 0, 1
A very common silicone that gives both skin and hair a silky smooth feel. It also forms a protective barrier on the skin and fills in fine lines. Also used for scar treatment. [more]
what‑it‑does buffering
An AHA that comes from citrus fruits. It is usually used as a helper ingredient to adjust the pH of the formula. [more]
what‑it‑does perfuming
The generic term for nice smelling stuff put into cosmetic products so that the end product also smells nice. It is made up of 30 to 50 chemicals on average. [more]
what‑it‑does preservative
A preservative that works mainly against fungi. Has to be combined with other preservatives. [more]
what‑it‑does buffering
Lye - A solid white stuff that’s very alkaline and used in small amount to adjust the pH of the product.  [more]
what‑it‑does surfactant/cleansing | viscosity controlling
what‑it‑does viscosity controlling
irritancy, com. 0, 1
A handy white powder that magically converts a liquid into a nice gel formula. [more]
what‑it‑does viscosity controlling
what‑it‑does viscosity controlling | surfactant/cleansing
what‑it‑does exfoliant | anti-acne | soothing | preservative
One of the gold standard ingredients for treating problem skin. It can exfoliate skin both on the surface and in the pores and it's a potent anti-inflammatory agent. [more]
what‑it‑does moisturizer/humectant
what‑it‑does perfuming
A colorless or yellowish oil that's used as a fragrance with a spicy scent. [more]
what‑it‑does perfuming | solvent
A super common fragrance ingredient found naturally in many plants including citrus peel oils, rosemary or lavender. It autoxidizes on air exposure and counts as a common skin sensitizer. [more]
what‑it‑does viscosity controlling
irritancy, com. 0, 0
A cellulose (the big molecule found in the cell wall of green plants) derivative that is used as an emulsion stabilizer and thickener. 
what‑it‑does emollient | emulsifying
It's quite the multi-tasker: an emollient and water-binding ingredient but also an emulsifier and can be used for stabilization purposes. It's also often used to create liposomes.  [more]
what‑it‑does buffering
what‑it‑does buffering
what‑it‑does antimicrobial/antibacterial | perfuming
Lavender - essential oil with a calming scent and antimicrobial properties. Contains fragrant components (linalyl acetate - 50% and linalool - 35%) and might be cytotoxic from 0.25%. [more]
what‑it‑does preservative
Preservative with relatively high irritation risk that is used mainly in rinse-off products. [more]