The AHA 2 BHA 2 Blemish Treatment
The AHA 2 BHA 2 Blemish Treatment
Product Description
Product overview
A clinically tested spot treatment serum pre-soaked into pure cotton balls, combining 2% Glycolic Acid (AHA) and 2% Salicylic Acid (BHA) with PHA and Zinc PCA to target blemishes, blackheads, and whiteheads with precision and minimal irritation.
Precision Spot Treatment
Pre-soaked cotton balls let you target blemishes directly without touching or contaminating the product, reducing the risk of overexfoliation on healthy skin.
Texture & feel
SENSORYPrecision Spot Treatment
Pre-soaked cotton balls let you target blemishes directly without touching or contaminating the product, reducing the risk of overexfoliation on healthy skin.
Triple Acid Power (AHA + BHA + PHA)
2% Glycolic Acid exfoliates surface skin, 2% Salicylic Acid penetrates pores to clear sebum, and Gluconolactone (PHA) gently soothes and hydrates without irritation.
Clinically Proven Results
In clinical trials on 20 subjects, achieved 75.76% reduction in pustules and 67.15% reduction in papules after just 4 weeks of use.
Hygienic Cotton Ball Design
100% pure compressed cotton balls expand with serum upon opening. Includes tweezers for completely contactless, sanitary application every time.
Safety & compatibility
SAFEContains 2% Salicylic Acid (BHA). Topical SA at 2% or below is generally considered low-risk by ACOG, but as a leave-on spot treatment, consult your healthcare provider before use during pregnancy or breastfeeding.
Contains Polysorbate 20, a surfactant that may feed Malassezia yeast. Not recommended for those with active fungal acne or pityrosporum folliculitis.
Rated 1/5. Oil-free, silicone-free formula with no heavy emollients. Unlikely to clog pores for the vast majority of skin types.
Free from parabens, sulfates, phthalates, fragrance, mineral oil, and alcohol. Hypoallergenic and dermatologist tested.
AHA (Glycolic Acid) increases photosensitivity. Always apply SPF 30+ sunscreen during daytime when using this product.
Contains active exfoliating acids. Apply to a small area first and wait 24 hours to check for sensitivity before using on blemishes.
Ingredient breakdown
INGREDIENTSGlycolic Acid (AHA) 2%Proven
The most researched Alpha Hydroxy Acid, derived from sugar cane. Dissolves the bonds holding dead skin cells together, revealing smoother, brighter skin underneath and boosting natural collagen production.
- Mechanism: Breaks down intercellular bonds in the stratum corneum to accelerate cell turnover
- Optimal pH: Works best at pH 3-4, which this product maintains for effective exfoliation
- Bonus: Stimulates hyaluronic acid production in skin for improved hydration
Salicylic Acid (BHA) 2%Proven
The gold standard Beta Hydroxy Acid for acne treatment. Oil-soluble, allowing it to penetrate deep into pores to dissolve sebum buildup, clear blackheads, and reduce inflammation. Also has anti-inflammatory properties similar to aspirin.
- FDA-Recognized: 0.5-2% concentrations are recognized by the U.S. FDA as effective OTC acne treatments
- Oil-Soluble: Unlike AHAs, can penetrate into oil-filled pores for deep cleaning
- Anti-Inflammatory: Calms inflamed and irritated skin, reducing redness around blemishes
Gluconolactone (PHA)Promising
A next-generation Poly Hydroxy Acid that gently exfoliates like traditional AHAs but with a larger molecular structure, causing significantly less irritation. Also acts as a humectant and antioxidant.
- Gentler Exfoliation: Larger molecule size means slower, less irritating penetration than AHAs
- UV Protection: A 2004 study found Gluconolactone helped prevent UV damage in skin cells
- Barrier Support: Moisturizes while exfoliating, helping repair impaired skin barriers
Zinc PCAPromising
A synergistic complex of Zinc and L-Pyrrolidone Carboxylic Acid that normalizes sebum production and demonstrates antimicrobial activity against the P. acnes bacteria responsible for acne breakouts.
- Sebum Control: In-vivo testing showed statistically significant sebum reduction after 28 days at 1%
- Antibacterial: In-vitro antimicrobial activity against P. acnes at 0.1-0.25% concentrations
- Anti-Aging: 2011 research suggests it may support Type I collagen production
AllantoinProven
A well-established soothing and skin-protecting ingredient that calms irritation caused by active exfoliating acids. Promotes wound healing at higher concentrations and provides a protective moisture layer.
- Soothing: Reduces irritation and redness from AHA/BHA activity
- Wound Healing: Studies show it accelerates skin recovery and cell regeneration
Sodium HyaluronateProven
The salt form of Hyaluronic Acid with a smaller molecular weight for better skin penetration. Acts as a powerful humectant, binding up to 1,000 times its weight in water to keep treated areas hydrated.
- Deep Hydration: Smaller molecules penetrate skin more effectively than standard HA
- Barrier Support: Helps maintain moisture balance during active exfoliation
17 ingredients
Water, Propanediol, Polysorbate 20, Glycolic Acid, Salicylic Acid, Gluconolactone, Zinc PCA, Allantoin, Sodium Hyaluronate, Sodium Hydroxide, Dipropylene Glycol, Hydroxyacetophenone, Caprylyl Glycol, Ethylhexylglycerin, Dipotassium Glycyrrhizate, 1,2-Hexanediol, Disodium EDTA
Where it fits in your routine
ROUTINEUse as a spot treatment after toner on clean skin. Can be used AM and PM. Always follow with sunscreen during the day. Avoid layering with other strong actives (retinol, vitamin C, other acids) in the same routine.
How to use
HOW TO USEOpen & Soak
Remove the serum container lid and allow the compressed cotton balls to soak up the serum. The pure cotton balls will expand as they absorb the treatment.
Pick Up with Tweezers
Use the included tweezers/tongs to pick up a soaked cotton ball. This keeps the application hygienic and prevents contamination from your fingers.
Apply to Target Areas
Gently tap or press the cotton ball directly onto blemishes, blackheads, or whiteheads. For blackheads on the nose and chin, you may gently wipe across the area.
Follow Up
Allow the serum to absorb fully, then continue with your serum, moisturizer, and sunscreen (AM). No rinsing needed. For daytime use, always apply SPF 30+ sunscreen.
Who is it for?
WHOPerfect for you if:
- You have occasional breakouts and want a targeted spot treatment
- You struggle with blackheads on the nose, chin, or T-zone
- You want a hygienic, no-mess application for blemish care
- You prefer a gentle exfoliating treatment over aggressive acids
- You need a travel-friendly acne treatment
- You have oily or combination skin with clogged pores
- You want a body-friendly treatment for chest or back blemishes
Consider alternatives if:
- You have active fungal acne (contains Polysorbate 20)
- You need a full-face exfoliating treatment (this is a spot treatment)
- You have severely compromised or damaged moisture barrier
- You are pregnant or breastfeeding (consult your doctor first)
- You want higher concentration acids for advanced exfoliation
- You have extremely dry or dehydrated skin without oiliness
Skin type compatibility
SKIN TYPESIdeal match. BHA penetrates oily pores, Zinc PCA controls sebum, and the lightweight formula absorbs instantly with zero shine.
Spot treatment format is perfect for targeting oily T-zone blemishes without drying out cheeks or other dry areas.
Clinically proven to reduce papules, pustules, blackheads, and whiteheads. Non-comedogenic formula won't trigger new breakouts.
Gentle 2% concentrations with soothing Allantoin and PHA. Fragrance-free and hypoallergenic, but always patch test first.
Contains Sodium Hyaluronate for hydration, but AHA/BHA can be drying. Use sparingly as spot treatment only and follow with a rich moisturizer.
Results timeline
WEEK 5-8Immediate Soothing & Calming
Active blemishes feel calmer and less inflamed. The BHA begins penetrating pores and dissolving sebum buildup. Slight tingling is normal during application.
Most users noticed soothing effectVisible Blemish Reduction
Whiteheads and surface blemishes begin to flatten and heal faster. Blackheads start loosening as AHA dissolves surface dead skin and BHA works inside pores.
~30% noticed reduction in whiteheadsClinically Measured Improvements
Significant clearing of papules and pustules with measurably reduced sebum production. Skin texture becomes smoother in treated areas, and pores appear less congested.
75.76% reduction in pustules (clinical trial)Sustained Clarity & Prevention
Continued use helps prevent new blemish formation. Oil control improves across treated zones. Post-acne marks begin to fade as skin cell turnover accelerates.
41.82% improvement in oil control (clinical trial)Ratings by platform
1K+ REVIEWSPros & cons
BALANCEDPraised
- Hygienic cotton ball format prevents contamination and overexfoliation
- Clinically proven to reduce papules by 67% and pustules by 76% in 4 weeks
- Short, clean ingredient list with only 17 ingredients
- Triple acid approach (AHA + BHA + PHA) for comprehensive exfoliation
- Gentle enough for daily use on most skin types
- Travel-friendly and compact packaging
- Affordable K-beauty price point
- Works on body blemishes too (back, chest)
Criticized
- Cotton balls can dry out if jar is not sealed tightly
- Only 30+ cotton balls per jar; heavy users run out fast
- Not fungal acne safe due to Polysorbate 20
- 2% concentrations may be too mild for severe or cystic acne
- Spot treatment only; not a full-face exfoliant
- Tweezers included are flimsy and hard to grip
Budget-friendly alternatives (dupes)
DUPESBHA-only pads without AHA or PHA. Stronger exfoliation with menthol, but more drying and potentially irritating. 55 pads per box offers much better per-use value. Not fragrance-free.
Dramatically higher AHA concentration (30% vs 2%). Full-face peel used only 1-2x per week for 10 minutes max. Much more intense; not for daily spot treatment. Fungal acne safe.
Full-face toner format with AHA, BHA, and PHA in lower concentrations. Tea tree oil based. Better for overall skin maintenance than targeted spot treatment. Larger 150ml bottle.
Comparison with competitors
SIDE-BY-SIDEStorage & shelf life
12 MONTHS12 months after opening
Store in a cool, dry place away from direct sunlight. Seal jar tightly after each use to prevent cotton balls from drying out.
Jar with lid containing compressed pure cotton balls and serum, includes tweezers/tongs for hygienic removal
Yes, compact 50g jar is under 100ml/3.4oz TSA limit. Ideal for on-the-go spot treatments.
Frequently asked questions
FAQThis product contains 2% Salicylic Acid (BHA), which is a member of the aspirin family. While the American College of Obstetricians and Gynecologists (ACOG) considers topical salicylic acid at 2% or below to be low-risk during pregnancy, many dermatologists recommend extra caution with leave-on BHA products. Since this is a spot treatment with minimal skin coverage, the absorption is very low. However, we recommend consulting your OB-GYN or dermatologist before using during pregnancy or breastfeeding. Azelaic acid and niacinamide are commonly suggested pregnancy-safe alternatives for acne.
No, this product is not considered fungal acne safe. It contains Polysorbate 20, a surfactant/emulsifier that can act as a food source for Malassezia yeast, potentially worsening pityrosporum folliculitis (fungal acne). If you have fungal acne, consider alternatives like The Ordinary AHA 30% + BHA 2% Peeling Solution (which is fungal acne safe) or a pure salicylic acid spot treatment without polysorbates.
Since this product already contains both AHA and BHA, avoid layering additional AHA or BHA products in the same routine to prevent overexfoliation and irritation. Do not use with retinol/retinoids at the same time—alternate between AM and PM or different days. Vitamin C (L-Ascorbic Acid) can also interact with acids; use vitamin C in the morning and this treatment in the evening for best results. Niacinamide is generally safe to combine with this product.
This product is best suited for oily, combination, and acne-prone skin types. The BHA component is particularly effective at penetrating oily pores, while Zinc PCA helps control excess sebum. Sensitive skin types can use it with caution (patch test first) thanks to the gentle 2% concentrations and soothing ingredients like Allantoin and Gluconolactone. Dry skin types should use sparingly and follow with a hydrating moisturizer, as AHA/BHA can be drying.
Many users notice initial soothing and calming effects within the first few days. Visible reduction in active blemishes typically occurs within 1-2 weeks. Clinical trials showed significant results after 4 weeks: 67.15% reduction in papules, 75.76% reduction in pustules, 27.27% reduction in blackheads, and 29.86% reduction in whiteheads. For sustained prevention and oil control improvement (up to 41.82%), consistent use over 4-8 weeks is recommended.
Apply after cleansing and toner, before serums and moisturizer. The order is: Cleanser → Toner → This Product (spot treatment) → Serum → Moisturizer → Sunscreen (AM). Since it's a spot treatment, apply only to targeted blemish areas using the provided cotton balls and tweezers. Allow it to absorb before applying the next step. Always finish with sunscreen during the day, as AHA increases sun sensitivity.
No, this product has a very low comedogenic rating of 1/5. The formula is oil-free, silicone-free, and contains no heavy emollients that typically clog pores. In fact, the active ingredients (Glycolic Acid and Salicylic Acid) are specifically designed to unclog pores and remove dead skin cell buildup. Zinc PCA further helps by regulating sebum production. It is considered non-comedogenic and suitable for acne-prone skin.
The product has a Period After Opening (PAO) of 12 months. However, since the cotton balls can dry out once the jar is opened, it's important to seal the lid tightly after every use. If the cotton balls begin to dry out, you can carefully pour the remaining serum from the bottom of the jar over them. The jar contains 50g of product with 30+ cotton balls. With daily spot treatment use, most users find a jar lasts approximately 1-2 months.
Verdict: The COSRX AHA 2 BHA 2 Blemish Treatment Serum is a clever, well-formulated spot treatment that stands out for its hygienic cotton ball delivery system and clinically backed results. The triple acid formula (AHA + BHA + PHA) at gentle 2% concentrations makes it accessible for most skin types without the harsh side effects of stronger exfoliants. It's best for those with oily to combination, acne-prone skin who want a targeted approach rather than a full-face treatment. The clean, minimal 17-ingredient formula earns extra points, though the Polysorbate 20 rules it out for fungal acne sufferers. At around $17 for 30+ cotton balls, the per-use value is reasonable for a K-beauty treatment, but heavy users may find themselves repurchasing frequently. Overall, an excellent addition to any blemish-fighting routine.
Product Overview
Quick product notes are a great way to check if a product is free from commonly avoided ingredients by skincare enthusiasts. These preferences come about for different reasons depending on the ingredient such as personal experiences, sensitivities, health preferences & etc.
Just because a product is not free from a common preference does not mean it's a bad product! You can make a personal decision whether or not you want to use a product that contains these ingredients or not - click the labels of the preference to read more about them.
Quick Product Notes
Ever used a product that promised a certain effect but provided no results? It might not have contained any notable ingredients that could have been responsible for that promised effect. It doesn't matter what the marketing or packaging «promises» it can do, if it doesn't contain anything that can help - then the likelihood of it helping is low.
We help you identify key notable ingredients that have been shown to help with effects such as acne-fighting, brightening, UV-protection, wound healing & anti-aging to help you achieve your skincare goals smarter. Please note that different notable ingredients have varying levels of research behind them, some are extremely well proven yet some have mixed research in their efficacy.
Just because a product doesn't contain any notable ingredients doesn't mean it's bad. And a product with notable ingredients (or even many) doesn't necessarily guarantee the efficacy of the product performing these effects either. There are other factors such as ingredient quality, concentration and formulation that will ultimately determine this.
Be smart and use this as just a starting point for you to make more informed and smarter choices and compare it with reviews to see if the product is right for you
Notable Effects & Ingredients
Why are some products great for some people and horrible for others? Well everyone has different skin types and different reactions to the same ingredients.
We've identified a range of ingredients that are commonly regarded as potentially good or bad for those with Dry, Oily/Acne-Prone or Sensitive skin.
A product that contains good or bad ingredients for your skin type doesn't always flat out make the entire product good or bad for your skin. There are other factors such as ingredient quality, concentration and formulation that will ultimately determine your skins reaction.
One of the best ways to use this section is to troubleshoot products you've had bad experiences with in the past. Check if it contains any of the marked ingredients to point out suspect ingredients to avoid in the future!
Ingredients Related to Skin Types
Ingredient Safety Breakdown refers to the percentage % of ingredients in different risk categories as classified by EWG (Environment Working Group) if they are available. There are almost endless cosmetic ingredients and they are one of the few organisations globally that have assigned ratings to a lot of the more commonly used ingredients which is why we reference them.
EWG is seen by many to be more on the alarmist side in their assignment of health ratings resulting in rating ingredients as riskier than they actually are. We recommend using this a reference point rather than a strict guide of ingredient safety and to always do further research if into ingredients that you may find suspect.
Ingredient Safety Breakdown
Product ingredient list
| EWG | CIR | Ingredient Name & Cosmetic Functions | Notes |
|---|---|---|---|
| 1 |
Water
Solvent, Skin Conditioning
|
|
|
| 1 |
Propanediol
Solvent, Viscosity Controlling, Viscosity Decreasing Agent
|
|
|
| 3 |
Polysorbate 20
Surfactant, Emulsifying
|
|
|
| 4 |
Glycolic Acid
Ph Adjuster, Buffering Agent, Exfoliant, Exfoliating, Buffering
|
Promotes Wound Healing
Dark Spots
Texture
Pores
|
|
| 4 |
Salicylic Acid
Skin Conditioning, Masking, Fragrance, Hair Conditioning, Antidandruff Agent, Antiacne Agent, Denaturant, Preservative, Exfoliant, Keratolytic, Corn/Callus/Wart Remover
|
Pores
|







