Salicylic Acid

If you have ever struggled with let’s just call it “problem skin” (acne, blackheads, whiteheads and things like these) then most probably you are familiar with salicylic acid (SA). Even if the name does not ring a bell, you have probably used it. Next to benzoyl peroxide it’s the gold standard ingredient for treating problem skin. 

There are two reasons for that:

Reason #1: It can exfoliate skin both on the surface and in the pores
AHAs are very cool, but they are water soluble and cannot go into the pores. SA is lipid soluble and it can go right into the pores and shed the stuck, dead skin cells out from there. That’s really good for treating blackheads as well as preventing acne formation. 

This was confirmed also by a study that compared 8% AHA and 2% BHA for treating blackheads. AHA did not decrease the blackhead density statistically significantly, but BHA did.  

Reason #2: SA is a potent anti-inflammatory
SA in chemical structure is very similar to aspirin, and it does have similar anti-irritant and anti-inflammatory effect. That is helpful both for acne and rosacea.  

So SA is definitely an ingredient to try if you have oily or problem skin, but all in all, it’s more effective against blackheads than inflamed zits. For the latter one,  it’s only moderately effective, and benzoyl peroxide outperforms it by leaps and bounds. But they work in different ways, so a combination therapy is a great way to go to fight (and win) against acne. (In fact, it’s a good idea to combine SA not only with BP, but also with any other antibacterial agent like azelaic acid or mandelic acid.)

What else to know? 
For BHA to work like an exfoliant acidic pH is needed, just like for AHAs. It can work optimally between pH 3-4. Above that it’s still useful as an anti-inflammatory but not as a pore cleansing exfoliant. 

For at home use 0.5-2% SA is effective and these products are usually gentle enough for daily use. In fact, in the EU 2% is the maximum strength allowed in at home products. 

There are also professional BHA peels that go in the 20-30% range. Those can fade pigmentation, decrease surface roughness, reduce fine lines and of course, treat acne. 

Oh, and one more things: studies show that SA does not increase skin’s sun sensitivity, but it has photoprotective effects. Not that we want to tell you not to use sunscreen, because please do!

Bottom line: SA is a great exfoliant and anti-inflammatory and you should definitely give it a try if you have oily skin, large pores, blackheads or whiteheads. If you have acne it’s also useful, but it’s even better to use it in a combination therapy with an antibacterial agent like benzoyl peroxide or azelaic acid. 

• Leslie Baumann, MD, Cosmetic Dermatology, 2nd edition, Glycolic acid, 148o
• Seminars in cutaneous medicine and surgery, 10/2008; 27(3):170-6., Effective Over-the-Counter Acne Treatments
• Clin Cosmet Investig Dermatol. 2010; 3: 135–142., Applications of hydroxy acids: classification, mechanisms, and photoactivity