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Updated on July 18, 2023

Overview

What they are

These products are both reef safe facial treatments. They have a total of 4 ingredients in common

Cool Features

They both contain BHA

Suited For

They're both likely to be good for fighting acne, anti aging, dry skin, brightening skin, oily skin, reducing pores, scar healing and dark spots

Free From

They both do not contain any harsh alcohols, common allergens, fragrances, oils, parabens or sulfates

We independently verify ingredients, and our claims are backed by peer-reviewed research. Spot a product that needs an update? Let us know.

Kiehl's Truly Targeted Acne-Clearing Pimple Patch with Salicylic Acid
Paula's Choice 10% Azelaic Acid Booster
Paula's Choice 10% Azelaic Acid Booster
Facial Treatment
American Brand United States

Ingredient Info

Click any item below to learn more and see relevant ingredients

At a glance

Click on any of the items below to learn more

Notable Ingredients

Benefits

Concerns

Notable Ingredients

Benefits

Concerns

Ingredients Side-by-side

found in both products
Truly Targeted Acne-Clearing Pimple Patch with Salicylic Acid
Salicylic Acid Masking, Preservative, Skin Conditioning
BHA IconPreservative IconGood for Oily Skin IconGood for Minimizing Pores IconGood for Scar Healing IconHelps fight Acne IconHelps brighten skin IconCan worsen Dry Skin IconMay cause irritation IconMay worsen Eczema IconMay worsen Rosacea Icon
BHABHA Icon PreservativePreservative Icon 5 Benefits 4 Concerns

Salicylic Acid (also known as beta hydroxy acid or BHA) is one of the most well-known ingredients for treating skin that struggles with blackheads and acne. It helps to exfoliate both the skin's surface and pores, and also acts as an anti-inflammatory agent.

Water Skin Conditioning, Solvent

Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.

Gluconolactone Skin Conditioning
PHA IconGood for Skin Texture IconHelps with Anti-Aging Icon
PHAPHA Icon 2 Benefits

Gluconolactone is a PHA. PHAs are a great gentle alternative to traditional AHAs.

Niacinamide Smoothing
Niacinamide IconGood for Oily Skin IconHelps reduce Skin Redness IconGood for Minimizing Pores IconGood for Dark Spots IconHelps fight Acne IconHelps brighten skin Icon
NiacinamideNiacinamide Icon 6 Benefits

Niacinamide has emerged as an all-star ingredient due to its many benefits.

Butylene Glycol Humectant, Masking, Skin Conditioning
1 / 0

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

1 Com. / 0 Irr.
Glycolic Acid Buffering
AHA IconGood for Oily Skin IconGood for Skin Texture IconGood for Minimizing Pores IconHelps with Anti-Aging IconGood for Dark Spots IconGood for Scar Healing IconHelps brighten skin IconMay cause irritation IconMay worsen Rosacea Icon
AHAAHA Icon 7 Benefits 2 Concerns

Glycolic Acid is arguably the most famous AHA with a ton of research to back up its benefits.

Sodium Hydroxide Buffering

Sodium Hydroxide is also known as lye or caustic soda. It is used to adjust the pH of products; many ingredients require a specific pH to be effective.

Glycerin Humectant, Skin Conditioning, Skin Protecting
0 / 0 Helps hydrate Dry Skin IconHelps brighten skin Icon
2 Benefits

Glycerin is already naturally found in your skin. It helps moisturize and protect your skin.

0 Com. / 0 Irr.
Methyl Gluceth-20 Humectant, Moisturising

Methyl Gluceth-20 is a humectant. Humectants help draw moisture from the air to your skin.

Hydroxyethylcellulose Emulsion Stabilising, Stabilising

Hydroxyethylcellulose is used to improve the texture of products. It is created from a chemical reaction involving ethylene oxide and alkali-cellulose. Cellulose is a sugar found in plant cell walls and help give plants structure.

Caprylyl Glycol Emollient, Humectant, Skin Conditioning

Caprylyl Glycol is a humectant and emollient, meaning it attracts and preserves moisture.

Dipotassium Glycyrrhizate Humectant, Skin Conditioning
Helps reduce Skin Redness IconHelps reduce irritation IconGood for Dark Spots Icon
3 Benefits

Dipotassium Glycyrrhizate comes from licorice root.

10% Azelaic Acid Booster
Water Skin Conditioning, Solvent

Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.

Azelaic Acid Buffering, Masking
Helps reduce Skin Redness IconGood for Minimizing Pores IconGood for Dark Spots IconGood for Scar Healing IconHelps fight Acne Icon
5 Benefits

Azelaic acid is a naturally occurring acid derived from grains. This ingredient is effective in treating acne, rosacea, and other skin conditions.

C12-15 Alkyl Benzoate Antimicrobial, Emollient, Skin Conditioning

C12-15 Alkyl Benzoate is made up of Benzoic Acid and long chain alcohols. It has a low molecular weight.

Disliked Full details ->
Caprylic/Capric Triglyceride Masking, Skin Conditioning

Caprylic/Capric Triglyceride is an emollient, solvent, and texture enhancer. It is considered a skin-softener by helping the skin prevent moisture loss.

Methyl Glucose Sesquistearate Emollient, Emulsifying, Skin Conditioning
Not safe for Fungal Acne Icon
Not safe for Fungal AcneNot safe for Fungal Acne Icon

Methyl Glucose Sesquistearate isn't fungal acne safe.

Very Disliked Full details ->
Glycerin Humectant, Skin Conditioning, Skin Protecting
0 / 0 Helps hydrate Dry Skin IconHelps brighten skin Icon
2 Benefits

Glycerin is already naturally found in your skin. It helps moisturize and protect your skin.

0 Com. / 0 Irr.
Cetearyl Alcohol Emollient, Emulsifying, Emulsion Stabilising
2 / 1 Fatty Alcohol IconMay worsen Oily Skin IconBad for Acne Prone Skin IconNot safe for Fungal Acne Icon
Fatty AlcoholFatty Alcohol Icon 3 Concerns

Cetearyl alcohol is a mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is mainly used as an emulsifier. Emulsifiers help prevent the separation of oils and products. Due to its composition, it can also be used to thicken a product or help create foam.

2 Com. / 1 Irr.
Very Disliked Full details ->
Glyceryl Stearate Emollient, Emulsifying
1 / 0 Not safe for Fungal Acne Icon
Not safe for Fungal AcneNot safe for Fungal Acne Icon

Glyceryl Stearate is a mix of glycerin and stearic acid.

1 Com. / 0 Irr.
Disliked Full details ->
Dimethicone Emollient, Skin Conditioning, Skin Protecting
1 / 0 Silicon Icon
SiliconSilicon Icon

Dimethicone is a silicone used for making products smooth and silky. It also has the added benefit of sealing in hydration. The amount of dimethicone found in beauty products is considered safe and non-comedogenic, meaning it won't clog pores.

1 Com. / 0 Irr.
Very Disliked Full details ->
Salicylic Acid Masking, Preservative, Skin Conditioning
BHA IconPreservative IconGood for Oily Skin IconGood for Minimizing Pores IconGood for Scar Healing IconHelps fight Acne IconHelps brighten skin IconCan worsen Dry Skin IconMay cause irritation IconMay worsen Eczema IconMay worsen Rosacea Icon
BHABHA Icon PreservativePreservative Icon 5 Benefits 4 Concerns

Salicylic Acid (also known as beta hydroxy acid or BHA) is one of the most well-known ingredients for treating skin that struggles with blackheads and acne. It helps to exfoliate both the skin's surface and pores, and also acts as an anti-inflammatory agent.

Adenosine Skin Conditioning
Helps with Anti-Aging IconGood for Scar Healing Icon
2 Benefits

Adenosine is in every living organism. It is one of four components in nucleic acids that helps store our DNA.

Glycyrrhiza Glabra Root Extract Bleaching, Emollient, Skin Conditioning
Good for Dark Spots Icon
Good for Dark SpotsGood for Dark Spots Icon

Glycyrrhiza Glabra Root Extract is an extract of the roots of Licorice. It has been found to have several benefits such as skin hydrating, conditioning, and soothing.

Boerhavia Diffusa Root Extract Skin Protecting
Helps reduce irritation Icon
Helps reduce irritationHelps reduce irritation Icon

Boerhavia Diffusa Root Extract comes from the Boerhavia Diffusa tree, or more commonly known as punarnava, red spiderling, spreading hogweed, or tarvine.

Unknown Full details ->
Allantoin Skin Conditioning, Skin Protecting, Soothing
0 / 0 Helps reduce Skin Redness IconHelps reduce irritation IconGood for Scar Healing Icon
3 Benefits

Allantoin plays a role in soothing and moisturizing the skin. Because of this, it is often added to products with strong active ingredients.

0 Com. / 0 Irr.
Bisabolol Masking, Skin Conditioning, Soothing
Helps reduce irritation Icon
Helps reduce irritationHelps reduce irritation Icon

Bisabolol is pimarily used to add fragrance to a product. However, it is also famous for helping soothe skin.

Cyclopentasiloxane Emollient, Skin Conditioning, Solvent
Silicon Icon
SiliconSilicon Icon

Cyclopentasiloxane is a silicone used to improve texture and trap moisture. An easier name for this is D5.

Disliked Full details ->
Xanthan Gum Emulsifying, Emulsion Stabilising, Gel Forming

Xanthan gum is used as a stabilizer and thickener within cosmetic products. It helps give products a sticky, thick feeling - preventing them from being too runny.

Disliked Full details ->
Sclerotium Gum Emulsion Stabilising, Skin Conditioning

Sclerotium Gum is a polysaccharide gum made by the fungus, Sclerotium rolfssii. It is similar to xanthan gum.

Disliked Full details ->
Propanediol Solvent

Propanediol helps absorb ingredients into your skin, boosting their benefits. It can act as an emollient, making your skin softer. Propanediol can help products last longer by boosting the properties of preservatives within the formulation.

Butylene Glycol Humectant, Masking, Skin Conditioning
1 / 0

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

1 Com. / 0 Irr.
Phenoxyethanol Preservative
Preservative Icon
PreservativePreservative Icon

Phenoxyethanol is a preservative that has germicide, antimicrobial, and aromatic properties. Studies show that phenoxyethanol can prevent microbial growth. By itself, it has a scent that is similar to that of a rose.

Very Disliked Full details ->

Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

Masking, Preservative, Skin Conditioning
Liked

Salicylic Acid (also known as beta hydroxy acid or BHA) is one of the most well-known ingredients for treating skin that struggles with blackheads and acne. It helps to exfoliate both the skin's surface and pores, and also acts as an anti-inflammatory agent.

This multitasking property makes it a great ingredient for cleaning out pores, controlling oil production, and reducing inflammation.

Unlike AHAs which are water soluble, Salicylic Acid is oil soluble. This means that it's able to exfoliate the inside of pores and reduce blackheads.

Concentrations of 0.5-2% are recognized by the U.S. FDA as an over-the-counter topical acne product.

It can cause irritation and/or dryness if one's skin already has a compromised moisture barrier, so it's best to focus on repairing that before introducing a Salicylic Acid into your routine.

In general, Salicylic Acid is a great ingredient for oily acne-prone skin.

While salicylic acid does not increase sun-sensitivity, we still recommend wearing SPF.

If you are looking for the ingredient called BHA or Butylated Hydroxyanisole, click here.

Learn more about Salicylic Acid
Skin Conditioning, Solvent
Loved

Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.

So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.

You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Stay hydrated!

Learn more about Water
Humectant, Masking, Skin Conditioning
Mixed

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

  • It is a solvent, meaning that it helps to dissolve other ingredients. This also enhances the absorption of the product into one's skin.
  • It is a humectant, which means that it helps attract moisture into the skin.
  • It helps improve product application.

Overall, Butylene Glycol is a safe and well-rounded ingredient. It is unlikely to irritate skin, and works well with pretty much all other ingredients.

Humectant, Skin Conditioning, Skin Protecting
Loved

Glycerin is already naturally found in your skin. It helps moisturize and protect your skin.

A study from 2016 found glycerin to be more effective as a humectant than AHAs and hyaluronic acid.

As a humectant, it helps the skin stay hydrated by pulling moisture to your skin. The low molecular weight of glycerin allows it to pull moisture into the deeper layers of your skin.

Hydrated skin improves your skin barrier; Your skin barrier helps protect against irritants and bacteria.

Glycerin has also been found to have antimicrobial and antiviral properties. Due to these properties, glycerin is often used in wound and burn treatments.

In cosmetics, glycerin is usually derived from plants such as soybean or palm. However, it can also be sourced from animals, such as tallow or animal fat.

This ingredient is organic, colorless, odorless, and non-toxic.

Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.

Learn more about Glycerin

Ingredient Ratings

Here's what our community thinks of the ingredients in these two products.

Truly Targeted Acne-Clearing Pimple Patch with Salicylic Acid
9
3
liked
mixed
disliked
not rated
10% Azelaic Acid Booster
9
2
9
1
liked
mixed
disliked
not rated

When to use

32 Routines
41% use in am
56% use in pm
69% use every day
When to use See routines that use it ->
490 Routines
43% use in am
57% use in pm
86% use every day
When to use See routines that use it ->

Reviews

Here's what our community thinks

Kiehl's Truly Targeted Acne-Clearing Pimple Patch with Salicylic Acid 12 ingredients

4.0 /5
from 3 ratings
No Scent (2) Sticky (2) Expensive (1)
MichelleR's avatar

MichelleR

7 months ago · Dry Skin
Review

Absolute perfect formula. It doesn't burn, and I wake up to results. Its too sticky to wear under makeup. I haven't tried it during the day or over...

Absolute perfect formula. It doesn't burn, and I wake up to results. Its too sticky to wear under makeup. I haven't tried it during the day or over makeup. But I love that it is clear. I highly recommend this product over any pimple patch. Pimple patches in public look awful! It's like wearing pajamas or a bonnet in public, save that for home!

P_55's avatar

P_55

17 days ago · Sensitive Skin
Review

Seems to help without causing irritation. Doesn't work as well as a pimple patch, but works well on emerging pimples. If you have an open newly...

Seems to help without causing irritation. Doesn't work as well as a pimple patch, but works well on emerging pimples. If you have an open newly popped pimple, use a pimple patch instead.

Paula's Choice 10% Azelaic Acid Booster 21 ingredients

3.5 /5
from 6 ratings
Broke Me Out (1) Doesn't Work (1) Irritating (1)
thesunrising's avatar

tretiMia

2 months ago · Normal Skin
Review

Did nothing for my fungal acne. Actually did nothing at all.
(Compared to my cheap no-name Russian brand Azelaic acid cream which worked wonders).

BubbIes's avatar

BubbIes

4 months ago · Combination Skin
Review

Paula's Choice at it again with cetearyl alcohol high up on the ingredient list. I'm disappointed by their ingredients fairly consistently now.