When I first tried this I absolutely hated it. I thought it would be like a toner, because it says "liquid". Instead, it has the consistency of Johnson's baby oil. My skin looked oily and felt sticky for a whole hour until I finally decided to wipe it off.
But then I changed my mind about it. The Neutrogena BHA does have some flaws: 2 percent salicylic acid and a ph of 3.6 is quite strong, and paired with the strong fragrance it is not the most gentle product (at least for daily use). So I tried this one instead.
What does salicylic acid do? When the ph-level is correct (3.2-3.6) it will exfoliate the skin as well as dissolving excess oil in the pores. Also, as an immediate effect it decreases the redness of acne spots and helps heal them faster.
At the beginning I did not notice whether this BHA, which is betaine salicylate at 4%, was actually working or not, because I also used my AHA toner whenever I have seen flakes of dead skin or blackheads. So I gave it some weeks. During that month (and I used it for more than a month) I realized I got more acne than usual, and the spots did not fade. And the BHA Liquid did not reduce the redness and it did not heal them quicker.
I had to use pore strips along with my AHA to keep my pores clean.
And now I am shocked because I tested the ph:
It is 6!
I have tested BHA products in the past and they always turned this paper bright red (ph3-4).
Officially, this product is said to have a ph of 4. It is not the first time, that a product claims to have a certain ph and then I test it and it is completely different. But this only happened to me with Asian products, mostly cleansers.
Great! This is what ph 4.0 looks like.
I am sorry for all this chemistry-lesson-like ph-testing but I am showing this to prove that the Cosrx BHA Liquid is ineffective as an exfoliant.
It does not mean it is completely useless. The BHA still works to reduce inflammation. But I am glad I have ph-strips lying around. I am not letting cosmetic companies fool me!
Luckily these days I started using a 12% mandelic acid serum and my nose is smooth again and the spots are fading. I guess if this works I will quit the BHAs altogether. They are either irritating or ineffective, in my experience.