PoreWise The Inkey List · Serums
Beta Hydroxy Acid Serum
Product
- Brand:
- The Inkey List
- Product type:
- Serums
- Last checked:
- 2026-10-30
- Formula version:
- Pack label · 2026-10-30
- Fragrance & alcohol:
- Fragrance-free · Alcohol-free
13 ingredients on this list · WATER at number 1 · PROPANEDIOL at number 2 · Betaine at number 3
Product description
A leave-on serum with 2% salicylic acid (BHA) for congested, blemish-prone skin.
Full ingredient list
Kept exactly as the source printed it, including spelling in the original.
- 1 WATER
- 2 PROPANEDIOL
- 3 BETAINE
- 4 SALICYLIC ACID
- 5 SODIUM HYALURONATE
- 6 ZINC PCA
- 7 PHENOXYETHANOL
- 8 HYDROXYETHYLCELLULOSE
- 9 MALTODEXTRIN
- 10 SODIUM HYDROXIDE
- 11 ETHYLHEXYLGLYCERIN
- 12 BIOSACCHARIDE GUM-1
- 13 TRISODIUM ETHYLENEDIAMINE DISUCCINATE
Original label text
Water (Aqua / Eau), Propanediol, Betaine, Salicylic Acid, Sodium Hyaluronate, Zinc PCA, Phenoxyethanol, Hydroxyethylcellulose, Maltodextrin, Sodium Hydroxide, Ethylhexylglycerin, Biosaccharide Gum-1, Trisodium Ethylenediamine Disuccinate
Ingredient analysis
SALICYLIC ACID · Actives · PROPANEDIOL · Humectants · SALICYLIC ACID · Exfoliants
Humectants
5Bind water and draw it into the upper layers of the skin.
Preservatives
3Inhibit microbial growth so the product stays safe to use.
Chelating agents
1Binds metal ions to keep the formula stable.
Evidence
- Skin effect Human trial Certainty: Moderate Primary source
In 83 adults with comedones, a serum containing salicylic acid and lipohydroxy acid significantly improved open comedones on the nose, closed comedones on the face, skin pore density, sebum secretion and skin hydration from baseline after 8 weeks; adding a mask improved closed comedones more than the serum alone (-6.56 vs -5.19, p = 0.022).
Who it applies to: Adults in Shanghai with comedones, PIE and PIH, using the serum for 8 weeks.
Study limits: Both groups used active products; improvements were reported against baseline and between the two active groups. Industry-funded. This is the trial found that counted open and closed comedones separately.
- Skin effect Clinical guideline Certainty: Moderate Primary source
The 2024 American Academy of Dermatology acne guideline lists topical salicylic acid as a conditional recommendation. Strong recommendations in the same guideline go to benzoyl peroxide, topical retinoids, topical antibiotics and oral doxycycline.
Who it applies to: Acne vulgaris in people aged nine and older, as covered by the guideline's scope.
- Skin effect Review article Certainty: Low Primary source
Against topical tretinoin, salicylic acid showed similar values in overall acne improvement (RR 1.00, 95% CI 0.92 to 1.09; one trial, 46 participants). The review graded the certainty of that finding as low.
Who it applies to: Topical salicylic acid for mild to moderate acne. Most participants in the review were 12 to 30 years old, and most studies ran longer than eight weeks.
Study limits: The review covers 49 trials with 3880 participants, salicylic acid appears in a small part of them: 41 to 86 participants per comparison. Every salicylic acid comparison was graded low or very low certainty.
- Skin effect Human trial Certainty: Very low Primary source
In a 21-day prospective study of 42 people with mild-to-moderate acne and oily or combination skin, a salicylic-acid-containing gel used twice daily was associated with a 23.65% fall in sebum, a 40.5% rise in skin hydration, a 49.26% fall in transepidermal water loss and a 23.81% improvement in acne grade (all P < 0.05 except IGA P < 0.001).
Who it applies to: Sebum, skin hydration, transepidermal water loss and acne grade over 21 days in people with oily or combination skin.
Study limits: One centre, 21 days, 37 of 42 participants were women, and the research group was affiliated with the product maker.
- Skin effect Brand claim Certainty: High Public database
Salicylic acid is a keratolytic: it loosens the bonds between dead skin cells so they shed.
Who it applies to: Acne and keratolysis, at the concentrations permitted for cosmetic use.
Study limits: Most evidence comes from leave-on acne treatments. A cleanser is on the skin for a minute. · Finding · SALICYLIC ACID
- Irritation Review article Certainty: Very low Primary source
Trials of topical salicylic acid for acne reported application-site reactions such as scaling and redness.
Who it applies to: Topical salicylic acid in acne trials, mainly leave-on use over eight weeks or longer.
Study limits: The review graded the salicylic acid adverse-event comparisons as very low certainty.
- Skin effect Human trial Certainty: Moderate Primary source
All five 0.1% hyaluronic acid creams tested, from 50 kDa to 2000 kDa, raised skin hydration and overall elasticity above the vehicle cream applied to the other eye at 60 days.
Who it applies to: 0.1% hyaluronic acid creams applied twice daily for 60 days to the eye area of women aged 30-60 with periocular wrinkles.
Study limits: Sixty days, and the vehicle sat on the fellow eye. Hydration and elasticity were read by instruments. The volunteers were women aged 30-60 with eye-area wrinkles.
- How deep it gets In vitro study Certainty: Moderate Primary source
Hyaluronic acid of 20-300 kDa crossed the stratum corneum in excised human skin, while hyaluronic acid of 1000-1400 kDa remained in the stratum corneum.
Who it applies to: Excised human skin with intact stratum corneum, measured by Raman micro-imaging after topical application.
Study limits: One laboratory's imaging study. Three molecular-weight grades were tested. "remains above" describes intact stratum corneum in this ex vivo setup.
- Skin effect Brand claim Certainty: Moderate Public database
Hyaluronic acid and its salt bind water at the skin surface, giving a plumper look immediately after application.
Who it applies to: Leave-on hydrating products.
Study limits: The effect is largely surface and temporary. In dry air a humectant. · Finding · Sodium hyaluronate · Hydrolyzed hyaluronic acid
- Legal limits Official legal text Certainty: High Primary source
The EU Scientific Committee on Consumer Safety concluded in 2016 that 2-phenoxyethanol is safe as a preservative at a maximum of 1.0%, which is the limit already set in Annex V/29 of the EU Cosmetics Regulation. It estimated a margin of safety of about 50 for children.
Who it applies to: Phenoxyethanol used as a preservative in cosmetic products, at or below 1.0%.
Study limits: The dossier behind the conclusion was submitted by Cosmetics Europe, the industry association, and the committee lowered the default toxicokinetic factor from 4.0 to 1.0 on its way to the 1.0% conclusion. The final opinion kept 1.0%.
Related skin concerns
Skin concerns with evidence for ingredients on this list.
Formula history
1 version of this formula on record.