Guide skincare - Ingredients

BHA (salicylic acid) - the ally for pores and imperfections according to a doctor and analyses by BeautyDecoders.

BHA, or salicylic acid, is a lipid-soluble exfoliant: it's the only acid that penetrates pores to unclog them, making it ideal against blackheads, acne and blemishes. It is also antibacterial, anti-inflammatory and sebum-regulating. In cosmetics, it is limited to 2 %; a pH between 3 and 4 guarantees its effectiveness. Like all exfoliants, it is photosensitizing: SPF 50 is mandatory.

FamilyBeta-hydroxyacid (fat-soluble)
MethodVerdict Sensitivity - Dr David's rule
Selection4 scrubs rated by BeautyDecoders

The properties of salicylic acid

BHA offers numerous advantages for getting rid of stubborn imperfections, unclogging pores and fighting pimples. But you need to know how to use it properly, make it part of your routine and choose the right products.

01

Liposoluble: enters pores

AHAs have a special feature that other acids do not. AHAs (glycolic, lactic) are water-soluble and act on the surface. BHA, which is fat-soluble, unclogs the inside of pores clogged with dead cells, sebum and residues - ideal for dilated pores and imperfections.

02

Antibacterial

It inhibits the growth of fungi, viruses and bacteria, including Cutibacterium acnes, certain strains of which are responsible for acne.

03

Anti-inflammatory & sebo-regulating

Inflammation is the main cause of a pimple's redness, swelling and size: acting on it gives a fairly rapid result. It also regulates sebum production, as the literature shows.

Regulations, formulation and frequency

European regulations limit the concentration of BHA in cosmetics to 2 %. However, pH and galenic formulations can be used to optimize efficacy and tolerance. A pH between 3 and 4 is ideal: effective without being too irritating. The galenic form also counts: a lotion is more effective than a gel, but the gel form is better tolerated.

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Like other exfoliating acids, BHA is photosensitizing: protect your skin with SPF 50.

How often should I exfoliate? This depends on the condition of the skin barrier, whether or not you already exfoliate, and your skin type. Healthy barrier, no other exfoliation, normal to oily skin: daily BHA is possible. As a precaution, start every other day. The golden rule: test, observe skin reaction and adapt your routine.

Which exfoliants with BHA ?

Here are four representative salicylic acid exfoliants, with BeautyDecoded scores and user feedback, from benchmark to gentle option for sensitive skin.

The ratings and review excerpts come from users of the BeautyDecoded application. These reviews are not verified. The Sensitivity Verdict applies the Dr David Rule: a sensitive skin score greater than or equal to 0 indicates a product suitable for sensitive skin, negative an increasing caution.
BHA 2% lotion - Paula's Choice

Paula's Choice 2% BHA Liquid Exfoliant

★★★★½4,74/5(31 reviews - very solid base)
The BHA reference for combination to oily skin

THE most-reviewed BHA reference (31 reviews): a fluid exfoliating lotion with 2 % salicylic acid that smoothes skin texture and unclogs pores. Ideal for combination to oily skin. Sensitive skin score -1.0 - slight caution. Refined texture and reduced imperfections according to the vast majority of feedbacks; some dry or very reactive skins find it too strong, to be adapted in frequency.

Scores BeautyDecoded
Dry skin
73,5
Oily skin
84
Normal to oily
91
Sensitive skin
-1
Imperfections
85
⚠ Sensitivity verdict Slight caution (score: -1.0). Adjust frequency on dry or reactive skin.
User feedback (31 reviews - representative extracts)
★★★★★«BHA is my favorite ingredient for my oily skin, I use it after double cleansing.»
★★★★★«Great on my teenager's grainy skin, smoothed skin texture.»
★★★★«Effective but a little strong at first, I've spaced out the applications and it's perfect.»
★★«Disaster for my skin, not suitable for dry and sensitive skin.»
Verdict - BHA's most popular reference: 2 % fluid lotion, which smoothes skin texture and unclogs pores (imperfections 85), for combination to oily skin. Slight caution (-1.0): adapt frequency to dry or reactive skin. 4.74/5 out of 31 reviews.
BHA 2% serum - Geek & Gorgeous

Geek & Gorgeous Porefectly Clear 2% Salicylic Acid

★★★★4,06/5(8 reviews)
The affordable alternative

BHA serum with 2 % salicylic acid, the accessible, well-formulated alternative, often compared to Paula's Choice for much less. For pores and imperfections, combination to oily skin. Sensitive skin score -1.0 - slight caution. Good value for money according to feedback; like all BHAs, results depend on the skin, with some not noticing a marked effect, and the smell is considered a little chemical.

Scores BeautyDecoded
Dry skin
81,9
Oily skin
84
Normal to oily
91
Sensitive skin
-1
Imperfections
85
⚠ Sensitivity verdict Slight caution (score: -1.0).
User feedback (8 reviews - representative extracts)
★★★★★«A good serum that doesn't fall short of a much more expensive Paula's Choice.»
★★★★«As good as the others, very good affordable brand.»
★★★«Pleasant but after six months, no clear improvement on my skin.»
★★★«Not really had any effect on my combination skin with irregular grain.»
Verdict - Well-formulated BHA 2 % serum, an affordable alternative often compared to Paula's Choice for less (blemishes 85). Slight caution (-1.0); results depend on the skin, odor a little chemical. 4.06/5 out of 8 reviews.
BHA 2% solution - The Ordinary

The Ordinary Salicylic Acid 21% Solution

★★★★½4,44/5(8 reviews)
Targeted minimalist - oily skin

The minimalist, affordable BHA solution with 2 % salicylic acid, effective for targeted treatment of imperfections. Reserved for oily skin (dry skin score very low at 11,9). Sensitive skin score -2.0 - unsuitable, Introduce gradually and do not overuse. Good targeted exfoliant according to feedback, but reactions are possible if overused or on already sensitized skin.

Scores BeautyDecoded
Dry skin
11,9
Oily skin
73,5
Normal to oily
73,5
Sensitive skin
-2
Imperfections
83,3
✕ Verdict sensitivity Not suitable for sensitive skin (score: -2.0). For oily skin only, do not overuse.
User feedback (8 reviews - representative extracts)
★★★★«Good exfoliant, but not to be used too much on sensitized skin.»
★★★★«I use it twice a week in combination with another skincare product, satisfied.»
★★★★«Effective as a targeted treatment for localized blemishes.»
★★★«Strong overnight reaction after a few months, red skin, use with caution.»
Verdict - Minimalist BHA 2 % solution effective in targeted treatment (blemishes 83.3), reserved for oily skin (dry skin 11.9). Unsuitable for sensitive skin (-2.0): do not overuse, possible reactions on sensitized skin. 4.44/5 out of 8 reviews.
PHA 4% + BHA - Geek & Gorgeous

Geek & Gorgeous Calm Down 4% PHA + BHA

★★★★★4,77/5(13 reviews - solid base)
Gentle exfoliator - for sensitive skin

Gentle exfoliant for sensitive skin: combines a PHA (large-molecule exfoliant acid, therefore gentler) with a small dose of BHA, for gentle exfoliation. Compatible with vitamin C in the morning. Sensitive skin score -1.5 - slight caution, but the best-tolerated exfoliator on this page. Reconciles reactive skin with exfoliation, according to enthusiastic feedback.

Scores BeautyDecoded
Dry skin
79,8
Oily skin
84
Normal to oily
91
Sensitive skin
-1,5
Imperfections
85
⚠ Sensitivity verdict Slightly cautious (score: -1.5), but the best-tolerated exfoliator on this page.
User feedback (13 reviews - representative extracts)
★★★★★«Ultra-gentle exfoliant that doesn't irritate my epidermis, perfect for my redness.»
★★★★★«A product that reconciles sensitive skin and exfoliation, my very reactive skin tolerates it.»
★★★★★«Gentle exfoliator, compatible with vitamin C in the morning, great combo.»
★★★★«Correct and smooth toner, pleasant for everyday use.»
Verdict - Gentle exfoliant: PHA (large molecules, softer) + small dose of BHA, exfoliates without aggressing (imperfections 85), compatible with vitamin C in the morning. Slightly cautious (-1.5) but best tolerated here, reconciles reactive skin with exfoliation. 4.77/5 out of 13 reviews.

With what combine BHA

01

BHA and AHA: alternate rather than accumulate

There's no need to use a BHA and an AHA on the same day. On the other hand, it can be useful to alternate: AHAs are more effective on visible signs of sun damage (spots, wrinkles). Two options: if the main problem is blemishes, use a BHA during the week and an AHA at weekends; if the problem is both acne and anti-aging, alternate BHA and AHA every other day or every third day.

02

BHA and vitamin C: the acidity combo

As part of an anti-aging routine, combine a BHA and a serum in the morning. vitamin C is very effective: we play on the acidity of both products to reinforce their potency. Low pH is a key criterion for the effectiveness of both vitamin C and exfoliants, and each benefits from the other's pH. In order: a very fluid exfoliant (lotion) should be applied before the vitamin C serum, a BHA gel afterwards.

03

The associations to avoid

Do not use at the same time as a BHA the retinol or the copper peptides They do not tolerate acid pH, which makes them ineffective. Separate them (morning/evening) or alternate them on different days.

Find the right BHA exfoliator for your skin profile.

The BeautyDecoded application lets you scan any cosmetic product to visualize its suitability for your skin type and needs, based on INCI analysis.

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Your questions about BHA

BHA or AHA: which to choose?
BHA (salicylic acid) is fat-soluble and penetrates pores: ideal for acne, blackheads and dilated pores. AHAs (glycolic, lactic) are water-soluble and act on the surface: better for spots, wrinkles and texture. For oily skin with imperfections, start with BHA.
Can BHA be used every day?
Yes, if your skin barrier is healthy, your skin is normal to oily and you don't exfoliate. If you're just starting out or have sensitive skin, start every other day and increase as tolerated.
Does BHA make skin sensitive to the sun?
Yes, like all exfoliating acids, BHA is photosensitizing. Sun protection with SPF 50 in the morning is essential, otherwise spots and skin damage may occur.
Is BHA suitable for sensitive skin?
Use with caution. Pure salicylic acid can irritate reactive skin. For them, it's better to use a gentle PHA + BHA formula, at low frequency, and always keeping an eye on the skin's reaction.

For go further

  • Lu J, et al. Salicylic acid treats acne vulgaris by suppressing AMPK/SREBP1 pathway in sebocytes. Exp Dermatol. 2019;28(7):786-794. PMID: 30972839.
Dr Sylvain DavidPlastic and aesthetic surgeon - Founder of BeautyDecoded

Information for educational purposes only. It does not replace a medical consultation and must be adapted to each individual. The compatibility scores generated by the application do not prejudge the individual tolerance of each skin type. Salicylic acid (BHA) is a photosensitizing exfoliant: daily SPF 50 sun protection is essential. It should be introduced gradually, and should not be combined with other exfoliants on the same day, or used simultaneously with retinol or copper peptides. In the case of sensitive skin, severe acne or skin pathology, dermatological advice is recommended. A tolerance test before first use is recommended.