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Paula's Choice BHA 9 Treatment

BHA 9 Treatment

This unique, concentrated leave-on BHA exfoliant with salicylic acid works wonders to improve the appearance of stubborn skin concerns such as enlarged or clogged pores, bumps, and patches of rough, dry skin. It’s suitable even for skin prone to milia.
Uploaded by: franfrensky on

Paula's Choice BHA 9 Treatment
Ingredients explained

What-it-does: moisturizer/humectant, solvent | Irritancy: 0 | Comedogenicity: 0
  • It's a helper ingredient that improves the freeze-thaw stability of products
  • It's also a solvent, humectant and to some extent a penetration enhancer
  • It has a bad reputation among natural cosmetics advocates but cosmetic scientists and toxicology experts do not agree (read more in the geeky details section)
Read all the geeky details about Propylene Glycol here >>

What-it-does: surfactant/cleansing

We don't have description for this ingredient yet.

A smallish polymer molecule (created from repeated units of Polyethylene glycol, aka PEG) that's used as a solubilizer and viscosity control agent.

It is a clear, colorless liquid that is water-soluble and water-binding (aka humectant) and can help to solubilize sparingly-water soluble things (e.g. vanilla, perfumes) into water-based formulas. Thanks to its water-binding ability, it also prevents the drying out of formulas, especially when combined with the fellow hygroscopic agent, sorbitol

Also-called: Aqua;Water | 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. 

Salicylic Acid⁠ - superstar
Also-called: BHA;Salicylic Acid | 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 >>

Glycerin⁠ - superstar
Also-called: Glycerol;Glycerin | 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 for dry skin at higher concentrations up to 20-40%
  • High-glycerin moisturizers are awesome for treating severely dry skin
Read all the geeky details about Glycerin here >>

Also-called: Oat Kernel Extract, Colloidal Oatmeal;Avena Sativa Kernel Extract | What-it-does: antioxidant, soothing, emollient, abrasive/scrub

When you hear oatmeal, you probably think of breakfast, but the finely ground version of whole oat kernels, aka colloidal oatmeal, can do good things for your skin, especially if it's dry, itchy or prone to skin-rashes or eczema.

Oat is loaded with compounds good for the body, inside or outside, such as soothing agent beta-glucan (5%),  lipids (3-11%) including barrier repairing omega-3 and 6 fatty acids or phenolic antioxidant and anti-inflammatory agents (avenanthramides). 

What-it-does: moisturizer/humectant, solvent | Irritancy: 0 | Comedogenicity: 1

Butylene glycol, or let’s just call it BG, is a multi-tasking colorless, syrupy liquid. It’s a great pick for creating a nice feeling product.  

BG’s main job is usually to be a solvent for the other ingredients. Other tasks include helping the product to absorb faster and deeper into the skin (penetration enhancer), making the product spread nicely over the skin (slip agent), and attracting water (humectant) into the skin.

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

Arginine⁠ - goodie

A semi-essential (infants cannot synthesize it, but adults can) amino acid that is one of the primary building blocks of hair keratin and skin collagen. It's a natural moisturizing factor, a skin hydrator and might also help to speed up wound healing

Arginine usually has a positive charge (cationic) that makes it substantive to skin and hair (those are more negatively charged surfaces) and an excellent film former.  Thanks to the positive charge, it also creates a complex with AHAs (AHAs like to lose a hydrogen ion and be negatively charged, so the positive and the negative ions attract each other) that causes a "time-release AHA effect" and reduces the irritation associated with AHAs

What-it-does: emulsifying, surfactant/cleansing | Irritancy: 0 | Comedogenicity: 0

It's a common little helper ingredient that helps water and oil to mix together. Also, it can help to increase the solubility of some other ingredients in the formula. 

What-it-does: chelating

Super common little helper ingredient that helps products to remain nice and stable for a longer time. It does so by neutralizing the metal ions in the formula (that usually get into there from water) that would otherwise cause some not so nice changes.

It is typically used in tiny amounts, around 0.1% or less.

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

what‑it‑does moisturizer/humectant | solvent
irritancy, com. 0, 0
A common glycol that improves the freeze-thaw stability of products. It's also a solvent, humectant and to some extent a penetration enhancer. [more]
what‑it‑does surfactant/cleansing
what‑it‑does moisturizer/humectant | solvent
A smallish polymer molecule that is used as a solubilizer and viscosity control agent in cosmetic products. [more]
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 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 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 antioxidant | soothing | emollient | abrasive/scrub
When you hear oatmeal, you probably think of breakfast, but the finely ground version of whole oat kernels, aka colloidal oatmeal, can do good things for your skin, especially if it's dry, itchy or prone to skin-rashes or eczema.Oat is loaded with compounds good for the body, inside or outside, such as soothing agent beta-glucan  [more]
what‑it‑does moisturizer/humectant | solvent
irritancy, com. 0, 1
An often used glycol that works as a solvent, humectant, penetration enhancer and also gives a good slip to the products. [more]
what‑it‑does skin-identical ingredient
An amino acid that is one of the primary building blocks of hair keratin and skin collagen. It's a natural moisturizing factor and might also help to speed up wound healing.  [more]
what‑it‑does emulsifying | surfactant/cleansing
irritancy, com. 0, 0
It's a common little helper ingredient that helps water and oil to mix together. Also, it can help to increase the solubility of some other ingredients in the formula. 
what‑it‑does chelating
Super common little helper ingredient that helps products to remain nice and stable for a longer time. It does so by neutralizing the metal ions in the formula (that usually get into there from water) that would otherwise cause some not so nice changes. [more]