Friday, February 19, 2010

Salicylic acid or beta-hydroxy acid

Sorry, the post for formulating with chrysanthemum extract got lost somewhere, and I don't have time to re-write it this morning (craft group went late, and I didn't get to sleep until MIDNIGHT! Woo! I'm such a party animal). So here's a post on one of my favourite ingredients, salicylic acid.

Salicylic acid (also known as B-hydroxy acid or BHA) is an orthohydroxybenzoic acid and the only BHA currently available to us to include in our creations. It is approved by the FDA at up to 2% in acne medications, but how does it really work?

Salicylic acid is a keratolytic (exfoliant), anti-fungal, anti-inflammatory, analgesic, and anti-itching ingredient we can add as a powder or as part of an extract like willow bark. It works by getting inside the sebaceous unit or pore of our skin and solubilizes the oils and other things inside it, so it's great for blackhead prone skin. It reduces the adhesion between the cells and encourages them to slough off, revealing nice, new skin cells. It works from the stratum corneum of our skin and works its way down to the lower layers.

Salicylic acid is a powerful anti-inflammatory, so it is great for any water based creation you might be making to help with inflammation, such as post sun exposure or wind chapping.

Salicylic acid helps our skin shed more readily, open clogged pores, and neutralize bacteria. It is used at 0.5 to 3% in acne related products, like cleansers, toners, and moisturizers. It can help with photodamaged skin thanks to its exfoliating qualities. It is a great inclusion in hair care products intended for dandruff prone hair. And it's a fantastic addition to something like an after shave lotion or tonic to reduce redness and inflammation, and prevent ingrown hairs.

Finally, salicylic acid helps with oil control, so it is good for products for people with really oily skin - hair care, facial care, and skin cleansers and moisturizers.

Start using salicylic acid at 1% for sensitive skin, 2% for normal skin, to see how you react. As salicylic acid is readily absorbed by our skin, it will boost the efficacy of the other fancy ingredients in your lotions and potions. So keep a record of how your skin reacts to it - it might love it, it might get irritated. And because it has an acidic pH, you might want to test your product to ensure it's in the right range if you're using a lot of it.

So why am I telling you all of this? Because tomorrow we're taking a look at willow bark extract and it contains a ton of salicylic acid!

As a note...Salicylic acid doesn't dissolve well in water, so you'll need to use an alcohol or a glycol like propylene glycol or butylene glycol, to dissolve it. You can use 20% ethanol - denatured alcohol or just some good ol' vodka or another less smelly alcohol - to dissolve 0.5% salicylic acid.

If you'd like to learn more about salicylic acid, check out this post on ULProspector for more information. 

Here are a few resources on how to dissolve 


Artisan Soaps said...

I really enjoyed reading this flip-side perspective on Salicylic Acid, you see my 8yr old is highly allergic to it so has to eat a very modified diet .. Imagine that, the boy can have all the sugar he wants but give him an apple or orange and the volume goes up, attention span disappears, doesn't sleep for days on end, and he gets nasty rashes on his face :(

It's refreshing to look at SA in a positive light instead of as the enemy :)

Thanks for sharing all your wonderful insightful knowledge with us - in ways we understand!

More Cowbell said...

Ooh. How are the salicylic acid levels in nectarines. Sounds like what happens to me when I eat them.

Would it be good in shampoos as an anti-inflammmtory? I get horrible rashes from shampoos. Sometimes I can only use a new one once or twice before the weeping sores hit. Wondering if tossing some of this in would help. Or do they already have that and is that what's causing me problems in the first place?

Meh. Always looking for a bandaid. Easier than doing the research. :)

Anonymous said...

is this not the same as Asprin? Could you crush up some asprin, or buy asprin powder and use it in formulations?

Susan Barclay-Nichols said...

Hi Artisan Soaps! Oh no. That must be so hard on him! It seems like everything in life has its downside and upside - like Botox. It's offering me amazing relief for my headache but it could be used as a deadly weapon.

Hi More Cowbell! I think some research is necessary. I'd hesitate to suggest salicylic acid as the answer to the problem. Are the shampoos store bought or made? If I were in your position, I'd make a list of the ingredients and try to find the ingredients that are similar. If the same ingredients - except water, of course - keep popping up, you might have your culprit there.

If you make your own, you could add some anti-irritating or mildness increasing ingredients like Crothix, a hydrosol, coco betaine, and so on. It could be a surfactant or it could be a conditioning agent, a protein, and so on. I think all you can do is experiment and see what works for you. Have you tried baby shampoo? It is very mild, but not the greatest cleanser for adult hair.

And a quick e-mail address is in the upper right hand corner of the side bar...

Hi Anonymous. I wouldn't. It's not pure salicylic acid, so you could end up adding things you don't want or things that might react with other ingredients in your product. It's not expensive stuff (although a pain to order if you're in Canada, because I've only ever seen it in suppliers in the States) and it's easy to add through various extracts.

Tara said...

Whenever I try to create a toner with salicylic acid (usually 2%), it ends up crystalizing in my final product (after a day or two). Is there something I am doing wrong?

Susan Barclay-Nichols said...

Hi Tara. When are you adding it to the toner? Are you heating your toner or whatever you're using to dissolve the salicylic acid? I haven't had this problem, so if you can give me more information, I might be able to help further.

Tara said...

Hey Susan - thanks for replying to my question. I dissolve the SA in the heated phase. It doesn't really dissolve otherwise, does it? Is it maybe because I refrigerate the toners after I make them? After I saw the crystallization, I took the toners out of the fridge to see if the crystals would go back into solution (and I can shake it back in, either). It would be great if you blogged about a step by step account of formulating with SA. I have so much of it that I would like to use up, but I find formulating with it to be a little frustrating!

Thanks again, Susan!

sfs said...

Hi Tara. I too have problems using salicylic acid in my formulas. My understanding is that it is only soluble in alcohol. I don't really like the idea of using isopropyl alcohol because it is so irritating. I am about to try dissolving it in heated glycerin. I'll let you know if I am successful. If anyone else has a better way to dissolve SA please let me know!

NBlakely said...

Hi Susan, I'm not sure if you'll get this comment or not but I have a question for you. I've also made a salicylic toner (using Alcohol and Witch Hazel) to use on my arms. I get a very weird rash kind of thing (Keratosis Pilaris)and NOTHING worked to get rid of it until I make my own concoction at a 5% stregnth. I know that is high, but it was for my upper arms and the over counter @ 2% (suggested by dermatologist) did not help. Anyway, it worked wonderfully, but after doing more research I'm concerned about the "grade" of Salicylic acid that I used. I obtained it from an online photography source ( I guess it is also used in processing film?). I understand this is not pharmaceutical grade but rather reagent grade? Is there a big difference, and do you think it is a matter of concern since I'm only using it for my upper arms not my face?

City Mouse said...

Hey there, great article. I am having a hard time finding a source for Salicylic Acid, I am in the U.S., can you recommend anyone?


Susan Barclay-Nichols said...

Hi City Mouse. I get mine from The Personal Formulator. I've checked a few other locations and couldn't find it at Lotioncrafter or the The Herbarie, although you can use white willow bark in its place.

Anonymous said...

Salicylic acid is only slightly soluble in water, one gram dissolves in 460mL water. To incorporate salicylic acid to a formulation, the following methods can be used: 1) it can be added to the oil phase of the emulsion and heated to 80-85C 2) it can be added to a water phase containing sodium phosphate, borax, alkali acetates or citrates to increase its solubility in water 3) it can be combined with a glycol, such as propylene glycol and alcohol If crystalization occurs over time, the concentration of salicylic acid in glycol may be too high. The typical use level of salicylic acid is 0.5-2%.

Salicylic acid can be added to Cream Base
To add salicylic acid to a cream base, you should first pre-mix it into propylene glycol. Also, if there are other ingredients with specific mixing requirements, please look into their individual solubility’s.

mariefel said...

hello susan if i will usa the SSA into a peeling cream...can u suggest how many percent should i give to SSA...

catherine said...

hi i've been researching solubility of salicylic acid and found this chart:

from this article:;year=2010;volume=4;issue=1;spage=60;epage=63;aulast=Maheshwari

i'm pretty sure in the chart "40% w/v" means % concentration in g/ml (so 40% w/v would be 40g/100 ml).

very handy to see the other things salicylic acid soluble in (glycerin, sodium citrate, etc)

if the links no longer work i saved in my email let me know if u want. :)

Susan Barclay-Nichols said...

Hi Catherine! Please e-mail me at and tell me which of the e-books you want as my thanks for these great links! Thanks for posting them!

Tara said...

Awesome Catherine! I have been looking for information like this for a LONG time! So happy to see this chart :-D

Anonymous said...

i brought water to a boil and the overall amount of salicylic acid i used completely dissolved but when i removed it from the fire it almost immediately recrystalised. Adding some baking soda completely dissolved it and it remained dissolved for ever. It literally helped with so many skin problems, even mosquito bites itching goes away.

My skin is so oily that even this high concentrate does not irritate my skin even the slightest.

Careful though, if you use the powder on your skin as it is it will definitely burn our skin, especially if you use it bare hands.

Sânziene şi Mătrăgună said...

great comment, Catherine!

I wonder what would be the perfect blend of solvents to dissolve 3% salicylic acid, without making the product sticky.. is propylene glycol also sticky? I have not used it yet....

Sânziene şi Mătrăgună said...

oh, or I could use a blend of urea and glycerin..

Kelli Spears said...

I realize this post is a couple years old but I hope I can still offer some help to a few people on the subject of Salicylic Acid. I have formulated three different products, face wash, toner and a face cream. I used 2% in the face wash and toner and just 1% in the face cream.
I purchased mine from the Personal Formulator but Ingredients to Die For carries 2 different types, one being water soluble, however, they have been out of stock on the water soluble type for a while now. They do offer a couple helpful tips when formulating with regular Salicylic Acid. One is a product called NatureSilk, which is an ester (INCI name Propanediol)that is water soluble and added to the heated water phase. They also carry a product called NatureCide which is Aspen Bark Extract. It is very high in Salicylic Acid and is listed in the Preservatives category as it offers some preservation capabilities as well.
I used NatureSilk in all three of my products and never had any problems with crystalization. I do heat and hold my water phase to 170 degrees Faranheit for 20 minutes.
I hope this information helps anyone who is having problems.
I would also like to say "Thanks" to Susan for sharing all of her great information, knowledge and ebooks. You have been an inspiration to me since I first began formulating.

Kelli Spears said...

I apologize if my first post was kind of confusing. I even previewed it.....twice! Duh!
I wanted to mention that NatureSilk is an emollient that also has solubilizing capabilities. It is listed under Surfactants and Solubilizers and it helps dissolve the Salicylic Acid in formulations.
NatureCide is Aspen Bark Extract that is very high in Salicylic Acid and can be used instead.
You really have to decide your budget due to the difference in cost. All three products have a lot of great benefits to offer formulators. NatureCide is quite expensive compared to Salicylic Acid. I use NatureSilk in many products due to its emollient properties,even if I am not using Salicylic Acid.
Sorry for any confusion in the first post.

Susan Barclay-Nichols said...

Hi Sanziene! You can try those things - I find glycerin a bit sticky in a toner, but fine in a lotion or face wash. I like propylene glycol, and I don't find it sticky.

Hi Kelli. Thanks for the information. I really hate it when suppliers call things their own names, rather than using the manufacturer's names or INCI names. I have used 1,3-propanediol and it's a good substitute for other humectants, like propylene glycol. It's called Zemea by the manufacturer and the INCI is Propanediol.

Zemea web page link

I don't know if I'd call it an emollient. I would call it a humectant for sure - it's on par with some of the really good humectants - and it is supposed to work well in that capacity. I have tried it - I prefer glycerin or sodium lactate, but it is a good choice if you want to draw water to your skin.

Great comment! Thanks, Kelli!

Anonymous said...

Salicylic acid is soluble in GRAIN alcohol. Such as Everclear (190 proof). Vodka doesn't work, sadly.

Rubbing alcohol (isopropyl) doesn't work, either.

This is just a heads-up, as some info on the net says it's soluble in alcohol but doesn't specify what type.

As a comment to the poster who wondered about using it for acne: Most acne preparations with SA on the market are about 2%. I have mixed as high as 10-12% for my son for his severe comedogenic acid. It worked a treat, used a couple times a week. He could have used 2% toner several times a day, but compliance was an issue with him ;-).

Sânziene şi Mătrăgună said...

Hi Susan,

Thanks - I will try Propylene Glycol - though I have no idea how to read the chart ... I want to dissolve 2% salicylic acid, how much PG should I use?

Michele said...

Michele said... I left this comment on another thread by accident so I'm reposting here!
Regarding the solubility of salicylic acid, it is actually soluble in oil (heated to at least 180) as well as alcohol / Propylene Glycol. I use it in a cleansing oil for refining my acne prone skin.

In answer to your question Susan on any studies or links re salicylic solubility in oil, my first source from some years ago was by DiSalvo R. 2002 Salicylic Acid, from The Chemistry and manufacture of cosmetics, Volume 111. Another was a really old but interesting article called Studies On Ointments II. Ointments Containing Salicylic Acid, Ernest A. Strakosch MD. The third source is myself! Salicylic Acid dissolves beautifully in Oil provided you heat it hot enough, no precipitates, no problems, I've been using it for years in my OCM and also facial oils.

Hope this helps someone.

October 27, 2013 at 12:08 PM

Anonymous said...

I know this is an old post but I came across it when trying to find out how on earth to use salicylic acid at 4-5% in my cream formulas without having to use lots of propylene glycol. Not that I have anything against PG, I just don't want to use loads of it because I don't like the feel then.

So, I'd like to thank Michele for the tip about dissolving SA in the oil phase. I never even thought of that. Can't wait to try it :)

Anonymous said...

Hi, I second what Anonymous said. SA is my #1 favorite special ingredient for daily skin care. I love Paula's Choice BHA liquid, but finally I'm trying to make my own. I wanted to find out how to dissolve SA in mineral oil for a simple anti-zit remedy. It kept separating back into a layer of powder at the bottom of the jar. I've used octylododecanol to dissolve it, following the advice on Making Cosmetics, and it works, but I'm afraid the octylododecanol is blocking my pores. It's listed as commodegenic on some of the comodogenicity lists, like this one: So now I will try heating up the oil and hopefully won't need the octylododecanol. Thanks Michele and everyone else for all the great info.

Mickey said...

Thank you, all you wonderful ladies! I hope someone may be able to clear this up for me. I have been looking online for the solubility of another great acid....Azelaic acid. I can only find conflicting info. Are all acids soluble in the same things? I mixed it in heated water and it seems to have dissolved. Its clear and tastes sour like acid does too. Can anyone please tell me for sure what azelaic acid will and wont dissolve in? Any other hot tips would also be appreciated! In reference to above, if you dissolve SA in grain alcohol, do you just incorporate it into an emulsion like that?
Thank you to my family of formulators!
And Susan, I love you and your kind, generous spirit!!


Katawomp said...

Wow what a great resource. I did some research by checking the msds sheet for Salicylic Acid first. Here's what it said regarding solubility:

Water/Oil Dist. Coeff.: The product is more soluble in oil; log(oil/water) = 2.3
Ionicity (in Water): Not available.
Dispersion Properties: See solubility in water, acetone.
p. 4
Soluble in acetone. Partially soluble in cold water. Very slightly soluble in hot water.

I also looked at the ingredients for some toner/astringent that I purchased. Among other things, it contains propylene glycol and alcohol (24.5%), glycerin, dimethicone propyl PG-Betaine, isoceteth-20, PEG-32, sodium citrate and water.

It would seem that several of these ingredients could help dissolve salicylic acid. My own concoction (created before all this research) was a dismal failure. I mixed together isopropyl alcohol and witch hazel with 2% salicylic acid. It appeared to dissolve initially, but crystals developed. After doing some research, I tried pouring my concoction (without heating the liquids) into my bottle of toner. The crystals did not dissolve.

So, has anyone come up with a way to dissolve salicylic acid in something other than oil that can be used as an astringent for oily skin?

Sânziene şi Mătrăgună said...

Yes, I used 50% solvents. Propylene glycol, ethoxydiglycol and butylene glycol :)

Val said...

Thanks for the great article! I am trying to find info on max dissolution ratios and heat needed to dissolve AHA powder in a carrier oil. I am researching how to enhance my OCM oil blend. Michele I see has good results using BHA in a similar manner. (thanks Michele for posting your insights!! Very apprecaited!) My questions is in regard to her info posted above: "Salicylic Acid dissolves beautifully in Oil provided you heat it hot enough, no precipitates, no problems, I've been using it for years in my OCM and also facial oils"

I would like to dissolve my BHA in FCO at a high ratio, then add bit of that to my cleansing oil blend. Any suggestions or comments are appreciated! I have been experimenting and need some guidance. Thanks again for being such an amazing resource, Val

Anonymous said...


For sulability in water, I mig equal part natrium bicarbonate and salicylic acid and water. This turnes the salicylic acid into a salt, Wright is easily soulable in water. Do not mig too much at a time since you get a fizz reaction (from the barbonate releasing) and a water biprodukt that will easely evaporation when heatet a bit in a double boiler. Left on the bottom is White powder salicylic salt.

The salt I add in the cool down phase, no crystalisation.

I have Tried to find som artiklens in english to attach, but unfortunatly all my research and articles are in Danish, and I came up short finding anything to explained the reaction in english.

Maybe someone else could?

/Clara (Denmark)

Anonymous said...

Sorry it should say mix where it says mig..... Danish spell check when writing english is a bad combo :-)

Erika Šalčiūtė said...

Wow, finding this article and thread in like a gift for me!
I've been surfing the net for a month trying to find people who are experienced in using Salicylic acid in their products...

The thing is, I'm new. I have never tried making anything and I have zero necessary products. I'm planning to buy some from Mystic moments UK (I live in europe) and make a water based ointment/gel with SA.

I'm having trouble with wrapping my head around the ingredients I would need. Salicylic acid and distilled water, naturally, and then there are solvents: Propanediol and Propylene Glycol, right? If I mix these, would I get a liquid or more like a gel? Or do I need to add glycerin to make it more like a gel?
Also, do I need to use some preservative to prevent it from going bad?

If someone would offer a little bit of help with this I would be so grateful! If not, I guess I'll keep on researching and experimenting, like you all did:)

Susan Barclay-Nichols said...

Thanks for that suggestion, Clara!

Hi Erika! If you bought some propylene glycol and mixed in the salicylic acid, then added that to water - and a preservative!!! don't forget that!!! - you will have a liquid that's on par with water. If you add some glycerin, you'll still hae a product that's like water. If you want a gel, do a search on this blog for gels to learn how to make them with carbomers. You can try to use xanthan gum, but it's really sticky and unpleasant. (Some people don't mind it, but I can't stand gums!)

Please visit the newbies section of the blog to learn more about when we use preservatives. (The answer is you must use a preservative if you are using water or the product will be near water.) You can find out more about preservatives in the preservatives section.

Kevin said...


Is Sodium Salicylate a suitable alternative form for using Salicylic Acid? It's a salt of SA and dissolves easily in water.

Kevin said...

Is Sodium Salicylate a suitable alternative to SA? It's a salt of SA and dissolves easily in water and I think it can be added in the cool down phase.

Can SA be added directly to an oil (like Argan Oil)?

Melanie said...

I know this is an ancient post, but it's still one of the better sources for homemade formulations with salicylic acid, so I thought I'd share what worked for me.

My goal was to make a 100g of a 2% SA toner with minimal amounts of ethanol, as it is very drying to the skin. It took me four attempts, but I finally managed by dissolving 2g Salicylic Acid in 5g Propylene Glycol, heated to about 45C. Separately, I dissolved 1g sodium citrate in 80g water and heated to 60C. I slowly mixxed SA/PG mixture in W/SC mixture. I heated again back to 60C and added 0.5g Allantoin and 1.0g Panthenol. Annoying they wouldn’t dissolve, so added I 10g Vodka (40% ethanol) and mixed a hand mixer. Then I cooled to 40C and added my preservative. It worked! (I probably could have used something else at the end to dissolve the additives, but oh well.)

Sara B.F. said...

Here is a video demonstrating how you can incorporate salicylic acid into a cream/lotion by first making a paste with propylene glycol:

I am thinking about making a gel using liquid willow bark extract instead of salicylic acid powder. Thought it would be easier to use the liquid extract when there is no oil phase to help dissolve the SA powder.