COS DE BAHA Retinol Serum 60ml

Values: 100% Genuine (Adilsons policy) · Fragrance-Free (confirmed via INCI) · Vegan-Friendly* / Cruelty-Free* (brand-stated). No Pregnancy-Safe or FA-Safe badge is applied — see Safety Notice and Sensory sections.

Pros: supported with niacinamide and hyaluronate to buffer some dryness, Vitamin E antioxidant included, 60ml gives good longevity for a nightly-or-less active. Caveats: the brand's own marketed "2.5" designation for retinol strength is disputed by an independent reviewer who cites a 0.13% figure on the brand's own site; we could not independently verify either number in this research pass, and Adilsons' own live listing does not state a percentage — treat the real strength as unconfirmed and introduce cautiously regardless.

Classification: RED — not for under 16. Retinol drives accelerated cell turnover and collagen signaling aimed at photoaging and fine lines, processes that prepubescent and early-teen skin has no functional need for and that can cause disproportionate irritation on skin that has not yet developed the barrier resilience adults build up. Safe alternatives: for a teen wanting a gentle first active, see COS DE BAHA Peptide Serum or COS DE BAHA Galactomyces Serum, both verified in stock and free of exfoliating or retinoid actives.

Step 1 (When): PM only, starting 2-3 nights per week. Step 2 (How much): pea-size amount for the whole face. Step 3 (How): apply to fully dry skin, wait 20-30 minutes after cleansing if you're new to retinol.

Introduce this as the ONLY new product in your routine. Wait a full 14 days before adding anything else. This isolation window ensures you can identify whether any reaction is caused by this specific product.

1. Double cleanse if wearing SPF/makeup. 2. Wait until skin is fully dry (retinol on damp skin increases irritation for beginners). 3. COS DE BAHA Retinol Serum — pea-size amount. 4. Wait 2-5 minutes if sensitive. 5. Moisturizer to buffer. In a 4-night skin-cycling protocol, this occupies the Retinoid night, with Exfoliation on a separate night and two Recovery nights in between.

Technique: pat/press, do not rub. Skin state: fully dry skin for beginners; more tolerant users can apply on slightly damp skin. Wait time: 2-5 minutes before moisturizer if sensitive, otherwise 60 seconds. Hands deliver 100% of product versus roughly 30-40% absorbed by a cotton pad — use hands.

This is an encyclopedia map of all product types. You do not use all of these daily. You select modules based on your skin state.

Global rules: viscosity ladder thinnest to thickest, water-phase before oil-phase, treatments before seals. Wait-time defaults: watery layers 10-20s, serum layers 30-60s, retinoids need fully dry skin (wait 10 minutes after cleansing if sensitive). If the routine pills, stings, or feels heavy, reduce layers, not increase.

PM Maximum Stack: 1. Micellar pre-cleanse (optional). 2. Oil cleanser if wearing SPF/makeup. 3. Water cleanser, then wait until fully dry. 4. pH-prep toner (optional, skip if it stings on retinol nights). 5. Hydrating toner layers (optional). 6. Essence (optional). 7. Soothing/barrier serum (optional, e.g. before retinol on sensitive nights). 8. Anchor product — this Retinol Serum, applied to dry skin, wait 2-5 minutes if sensitive. 9. Targeted serum (optional, ONLY if non-conflicting — do not add another exfoliant or Vitamin C the same night). 10. Moisturizer. 11. Occlusive seal (optional, helps buffer dryness). 12. Spot treatment (as needed, on non-retinoid areas). Do not layer retinoids with AHA/BHA in the same night; keep one lane per night.

AM notes: this product is PM-only. AM should instead run an antioxidant/hydration lane and mandatory SPF50+ PA++++ — retinol increases photosensitivity, and any collagen-support gains are undone without daily sun protection.

Lane strictness: Retinoid OR Exfoliation OR Strong Vitamin C (LAA) OR Acne-control active per routine; barrier/hydration can always accompany.

Tier: light fluid serum. Layering rule: apply to dry skin as the active step, before moisturizer. Phase: water-based emulsion with Polysorbate 20 as an emulsifier/solubilizer for the retinol and Vitamin E fractions.

Rest days required: at least 2-4 non-retinol PM nights per week while building tolerance. Overuse warning: exceeding your current tolerance frequency does NOT produce faster results — it produces barrier damage, redness, and flaking that can set your timeline back weeks.

Purging vs. Reaction: PURGING occurs in your usual breakout areas, stays surface-level, and resolves in 4-6 weeks as turnover speeds up. A REACTION — new-area breakouts, burning, swelling, or hives that worsen rather than improve — means stop immediately and follow the 72-Hour Barrier Reset below.

Prerequisites: before starting this product, your routine MUST already include a daily SPF habit and a plain, tolerated moisturizer. Without these foundations, this product causes more harm than benefit.

Graduation ladder: if you are brand-new to retinoids, consider starting with COS DE BAHA Clearing Serum (a gentler combo formula that includes a lower-dose retinol alongside niacinamide, azelaic acid, and salicylic acid) before stepping up to this standalone, higher-positioned retinol serum.

Barrier index gate: if your skin stings on moisturizer, feels tight within 30 minutes of cleansing, or shows visible flaking, your barrier is below threshold — start with a barrier-repair product such as SKIN1004 Centella Probio-Cica Enrich Cream first.

Fine lines and texture: retinol accelerates keratinocyte turnover, resurfacing rough, dull texture over weeks. Uneven tone: supported by faster cell cycling and the included niacinamide. Secondary benefit: Vitamin E provides mild antioxidant support alongside the retinol. What it cannot do: it cannot lift sagging skin, cannot physically shrink pores, and cannot replace the speed or predictability of a prescription-strength retinoid if your dermatologist has recommended one.

Sunscreen (mandatory AM, non-negotiable with retinol): primary — Beauty of Joseon Relief Sun: Rice + Probiotics SPF50+; alternatives — SKIN1004 Centella Hyalu-Cica Water-Fit Sun Serum, Anua Heartleaf Silky Moisture SunCream, ROUND LAB Birch Juice Tone-Up Sunscreen.

Barrier-support moisturizer: primary — Dr.Althea 147 Barrier Cream; alternatives — SKIN1004 Centella Probio-Cica Enrich Cream, Beauty of Joseon Dynasty Cream, Anua Birch Moisture Boosting Cream.

Hydration buffer: primary — COS DE BAHA Hyaluronic Serum; alternatives — COS DE BAHA Galactomyces Serum, Anua Daily Relief Lotion, Beauty of Joseon Red Bean Water Gel.

This is a conflict-solver for ACTIVE ingredients. If you run multiple actives, use these rules to avoid irritation, deactivation, and barrier damage.

Universal rules: run only one primary active lane per routine (Retinoid OR Acid Exfoliation OR L-Ascorbic Acid Vitamin C OR Benzoyl Peroxide OR strong acne lane). If you break a rule, reduce frequency, split AM/PM, or alternate nights rather than pushing through. If moisturizer stings or skin feels tight within 30 minutes of cleansing, pause all actives and run barrier-only for 3-7 days.

× AHAs (Glycolic/Lactic/Mandelic) — never the same night; use skin cycling (AHA night → Retinol night → 2 Recovery nights) or alternate nights entirely.

× BHA (Salicylic Acid 0.5-2%) — avoid same night for most people; run BHA on non-retinoid nights, or BHA AM / Retinol PM.

× Benzoyl Peroxide (BPO) — do not layer, BPO can oxidize/deactivate retinol; run AM BPO / PM Retinol instead.

× L-Ascorbic Acid (pure Vitamin C) — don't layer in the same routine; classic split is AM Vitamin C / PM this Retinol Serum.

× Strong "Peel" Actives — never the same day; treat peels as their own lane, with 48-72h recovery before resuming retinol.

Scheduling templates: Template A (AM/PM Split) — AM antioxidant/Vitamin C + moisturizer + SPF, PM this Retinol Serum + moisturizer. Template B (4-Night Skin Cycling) — Night 1 Exfoliation, Night 2 Retinol, Nights 3-4 Recovery. Template C (Alternate-Night) — Mon/Wed/Fri Retinol, Tue/Sat Acid or BHA, Thu/Sun Recovery.

Do not layer retinoids with AHA/BHA in the same night; keep "one lane" per night. If unsure, default to the safest lane — barrier/hydration — and reduce layers.

MYTH: "A higher marketed retinol number always means a stronger, better product." REALITY: this product's own marketed "2.5" strength designation is disputed — position in the ingredient list (after an emulsifier typically used at 1-3%) suggests the true retinol fraction could plausibly be well under 1%, and we could not independently confirm either figure. Judge the product by how your skin responds, not by the number in its name.

MYTH: "Retinol purging and a bad reaction look the same." REALITY: purging happens in your usual breakout zones and resolves in weeks; a reaction shows up in new areas with burning, swelling, or hives and gets worse, not better — see the Results Timeline above.

Sweat carrying retinol-treated skin into direct sun without SPF is a common Mauritius-specific failure point — reapply sunscreen every 2 hours if outdoors. Mauritius tap water hardness varies by region; hard-water residue after cleansing can compound retinol dryness, so a pH-balancing toner beforehand is worth trying if flaking feels worse than expected.

*Concentration dispute: the brand's product name references "2.5," commonly read by shoppers as 2.5% retinol. One independent reviewer publicly alleged the brand's own website instead states 0.13% retinol — a significant discrepancy we could not independently verify via WebFetch (blocked in this environment). Adilsons' own live Shopify listing for this product does not state a percentage at all. Retinol's position in the INCI (8th of 18 ingredients, after Polysorbate 20, an emulsifier typically used at 1-3%) is more consistent with a sub-1% concentration than with 2.5%, though this is inference, not confirmation. We are treating the true concentration as unconfirmed rather than stating either number as fact.

Full INCI list: Water/Aqua, Propanediol, Niacinamide, 1,2-Hexanediol, Sodium Hyaluronate, Aloe Barbadensis Leaf Extract, Polysorbate 20, Retinol, Tocopheryl Acetate, Rosa Damascena Extract, Lavandula Angustifolia Flower Extract, Camellia Sinensis Leaf Extract, Melissa Officinalis Leaf Extract, Artemisia Vulgaris Extract, Undecane, Tridecane, Tocopherol, Disodium EDTA. [--- Estimated 1% Line ---] Estimated after Retinol/Tocopheryl Acetate — ingredients from Rosa Damascena Extract onward are estimated (not brand-confirmed) to sit below 1%.

Preservative system: 1,2-Hexanediol plus Disodium EDTA (chelating agent that supports preservative efficacy).

Fragrance status: Fragrance-Free (no Parfum/Fragrance listed). Scent: a faint herbal note is plausible from the rose/lavender/green tea/melissa/mugwort extracts, alongside the characteristic mild "retinol smell." Intensity: estimated 1-2 out of 5. EU 26 allergen screen: none of the 26 named allergen molecules detected as standalone listings; the botanical extracts present could carry trace natural allergens for extract-sensitive users. Alcohol disclosure: Alcohol-Free.

Halal: *Self-assessed by Adilsons based on available INCI data. No ethanol, no porcine-derived ingredients, and no haram animal-derived ingredients detected in the declared list. This is NOT a formal Halal certification.

Vegan: *Self-assessed by Adilsons based on available INCI data. No animal-derived ingredients detected (Tocopherol/Tocopheryl Acetate here are synthetic/plant-derived forms, not animal-sourced). This is NOT a formal vegan certification.

Cruelty-Free: *Brand-stated policy, not independently certified by Leaping Bunny, PETA, or equivalent audit.

Microplastic-Free: Yes.

MFDS Classification: not publicly confirmed. Clinical evidence: retinol as an ingredient class has 40+ years of published research for fine lines, texture, and tone — this is Strong ingredient-class evidence, but it does not confirm this specific product's dosing or a brand-run trial. Evidence confidence: High for the ingredient class, Low-Marketing-Only* for this product's specific "2.5" strength claim given the unresolved concentration dispute.

Fungal Acne Safety: FA-Conditional. Polysorbate 20 is a mild emulsifier some fungal-acne-prone users react to at higher concentrations; low risk for most people at typical serum use levels.

Assessment: Low-Medium. Retinol serums can pill if layered over an incompletely absorbed hydrating serum — wait the full 60 seconds to 2 minutes before this step, and use a thin layer of moisturizer afterward rather than a thick one.

Fresh color: pale yellow (retinol's natural color). Oxidation warning color: a shift to noticeably darker yellow, orange, or brown means the retinol has oxidized and generates free radicals instead of providing benefit — discard. Storage: keep tightly capped, away from light and heat above roughly 25-30°C; retinol is one of the more light/air/heat-sensitive actives in this brand's catalog. Spoilage signs: color darkening, separation, or an off smell.

Patch test: inner forearm for 24 hours, then behind the ear for 24 hours, then begin facial use at 1-2 nights per week. If adverse reaction: STOP ALL ACTIVES. For 72 hours, use ONLY gentle cleanser plus plain moisturizer plus mineral SPF — no acids, retinoids, Vitamin C, exfoliants, or essential oils. After 72 hours, reintroduce ONE product per 14 days. Emergency stop signals: hives, swelling, blistering, persistent burning, or breathing difficulty — seek emergency care. Pregnancy alternatives: if you are pregnant or nursing, consider COS DE BAHA Peptide Serum for gentle anti-aging support instead, and speak to your doctor about any active ingredient before use.

1. Starting nightly instead of building up from 2-3x/week. 2. Skipping sunscreen the next morning. 3. Layering with another acid or Vitamin C the same night. 4. Applying to damp, freshly-cleansed skin as a beginner. 5. Leaving the bottle uncapped or in direct light, accelerating oxidation. Overuse threshold: exceeding your current tolerance frequency does not speed results — it causes barrier damage that sets your timeline back.

Volume: 60ml. Amount per use: pea-size (~0.5ml). Approximate uses per container: roughly 100-120 applications. Lifespan: at 3x/week use, approximately 8-10 months; overdosing at nightly use both wastes product faster and increases irritation risk without added benefit. Reorder roughly 2-3 weeks before you expect to run out.

This serum's job is PM-only accelerated turnover and collagen signaling — it is the Retinoid lane anchor, never combined same-night with acids or Vitamin C. AM: antioxidant/hydration lane → moisturizer → mandatory SPF50+ PA++++. PM (retinol night): cleanse → dry skin → Retinol Serum → moisturizer. PM (recovery night): cleanse → hydrating/barrier serum → moisturizer only.

If your skin is barrier-compromised right now: repair first with a Centella-based cream before starting or resuming this. If you are in AC all day: increase your hydration-serum layer to offset retinol dryness. If you are new to retinoids entirely: start with COS DE BAHA Clearing Serum's lower-dose combo formula instead of this standalone serum.

After purchasing, you will receive our skincare education email series covering this product in depth. The recommendations above are based on formulation synergy with COS DE BAHA Retinol Serum, not on margin or stock levels. If a pairing does not exist in our catalog, we say so. If you already own a product that fills the same role, use what you have first.

If you want a gentler, multi-active entry point rather than a standalone high-positioned retinol, COS DE BAHA Clearing Serum (Niacinamide 10% + Azelaic Acid 5% + Retinol 0.1% + Salicylic Acid) is a real, in-stock alternative from the same brand at a lower retinol dose alongside other actives.

Choose this Retinol Serum over the Clearing Serum if you need a higher, standalone retinol dose without azelaic acid or salicylic acid competing for the same routine slot.

Upgrade triggers (if 2+ apply, this product is the better fit): you've used the Clearing Serum's 0.1% retinol for 8+ weeks without irritation; your main concern is texture/fine lines rather than active acne; you don't need azelaic acid's redness-reduction; you want a distinct product to alternate with an acid exfoliant on separate nights. Do not upgrade yet if: your barrier is currently compromised; you are new to retinoids entirely; you are also managing active acne (the Clearing Serum's combo may serve you better).

If you match 2 or more upgrade triggers above, this Retinol Serum is worth choosing. If not, the Clearing Serum is sufficient and safer. Consistency beats complexity.

A real strength ladder exists in this brand's catalog: COS DE BAHA Clearing Serum (0.1% retinol within a multi-active combo) → this COS DE BAHA Retinol Serum (higher, standalone dose) is the natural next step once tolerance is established, generally after 8+ weeks of irritation-free use at the entry level.

This product's PRIMARY function is: retinoid-driven accelerated turnover and collagen signaling. You do NOT need this if you already own another retinol/retinoid product, including COS DE BAHA's own Clearing Serum or the separate 30ml Retinol Serum — running two retinoid products simultaneously adds irritation risk without added benefit. Stacking assessment: No Benefit (same mechanism) if paired with any other retinoid; Significant Benefit if your current routine has no cell-turnover-driving active at all.

This product is sourced through authorized Korean distributors — primarily Craver Co., Ltd (South Korea), alongside other verified distribution partners. Craver is a major Korean beauty distributor and the parent company of SKIN1004, handling authorized distribution for multiple K-beauty brands. All products are shipped directly to Mauritius via verified channels.

For comprehensive information about how we verify authenticity, our layered verification system, and how to check your product at home, visit our dedicated Authenticity and Trust page. Because a separate 30ml Retinol Serum also exists in this brand's line, double-check the volume printed on your box matches what you ordered.

Parent Company: JAINA Co., Ltd (CEO Junwon Lee). Founded: 2019. Headquarters: Suwon, South Korea. Manufacturing: contract manufacturing in South Korean laboratories the brand states are MFDS-certified.

COS DE BAHA positions itself as a value/high-potency actives brand, selling clearly-labeled single- and combo-active serums at accessible prices relative to prestige K-beauty actives brands. This retinol serum sits at the higher-strength end of that catalog, alongside a gentler combo (Clearing Serum) and a separate 30ml standalone size.

Independent sources show a small, mixed sample for this exact product (approximately 2.7 out of 5 from only 3 ratings found — a very small sample, low confidence). One reviewer found it hydrating; another was uncertain it was working, found the texture uncomfortable, and felt it never fully absorbed, leaving skin feeling oily. Separately, a reviewer publicly raised the concentration-labeling discrepancy discussed above. We are not aware of a larger, more reliable review base for this exact SKU at the time of writing.

Is this really 2.5% retinol? We could not confirm this. The brand's product name references "2.5," but an independent reviewer alleges the brand's own site states 0.13%, and the ingredient's INCI position is more consistent with a lower concentration. Treat it as unconfirmed and introduce cautiously either way.

Can I use this in the morning? No — this is PM-only; retinol increases photosensitivity.

Can I use this while pregnant? No — see the Safety Notice at the top of this page.

Will I purge? Some users experience purging in usual breakout areas during weeks 2-6; this is different from a true reaction — see the Results Timeline section.

Can I combine this with Vitamin C or an acid toner? Not the same night — see the Conflict Solver section for the AM/PM split approach.

Retinol

A Vitamin A derivative that accelerates skin cell turnover and supports collagen signaling.

Retinization

The initial adjustment period (flaking, redness) as skin adapts to a new retinoid.

Purging

Temporary, accelerated surfacing of existing blockages in usual breakout areas, distinct from a true reaction.

Barrier

The skin's outermost protective layer; must be intact before introducing strong actives.

Polysorbate 20

A mild emulsifier used to blend oil-soluble ingredients like retinol into a water-based formula.

Every product sold by Adilsons Beauty is 100% genuine, sourced through authorized Korean distribution channels. Full details on our verification system: Authenticity and Trust.

Our team is available to help you build a routine, troubleshoot reactions, and answer ingredient questions. WhatsApp: +230 5 778 2336.

For in-depth skincare education, visit our blog at adilsons.mu/blogs/k-beauty or subscribe to our email to get our guided education series delivered to your inbox.

Coverage: Island-wide delivery (Mauritius).

Processing and Timing: Orders process in 1-2 business days; usually ready by Day 3 for pickup by our delivery partners/regional team. Partner collection can take up to 1 week. After pickup, delivery typically takes 1-5 business days (weekdays only).

Express: May be available by region; request on WhatsApp: +230 5 778 2336.

Liquids/Sensitive Items: Serums, toners, liquid makeup (and kits containing liquids) are pickup or door-to-door only; checkout enforces this.

Scheduling: Deliveries run by region on set schedules; we will contact you the evening before.

Pickup: Citadelle Mall pickup available.

Returns: No change-of-mind exchanges.

Refunds (Summary): For defective/damaged on receipt (report within 48h), wrong item, or manufacturing defect within 6 months. Refunds via bank transfer (7-10 business days); card refunds may incur a 5% processor fee (fee not charged for defects/order errors). Opened skincare/personal-care items are non-returnable (except if damaged on delivery).

Source of Truth: This is a quick snapshot. If anything differs, the policy pages are final.

Store Policies: For the most up-to-date information, please review our Shipping Policy and Refund Policy.

Best for: non-pregnant users age 16+ with an established barrier and daily SPF habit, wanting a standalone retinol step for texture and fine lines. Key benefits: niacinamide and hyaluronate support built into the formula, generous 60ml size, real ingredient-class evidence for retinol. Keep in mind: the marketed "2.5" strength is disputed and unconfirmed either way; PM-only with strict SPF required; not suitable during pregnancy/nursing or for under-16s.

Assessment: Not Suitable. This product contains a retinoid, which is generally avoided on treatment-sensitized or radiation-exposed skin due to increased irritation risk. Consult your oncology care team before introducing any new skincare products during treatment, and consider a fragrance-free, retinoid-free alternative such as COS DE BAHA Hyaluronic Serum instead.

Quick scanner: Week 1-2 — introduce alone at 2 nights/week, monitor for excess flaking/redness. Week 3-4 — increase to 3 nights/week if stable. Week 5+ — add one support product only if genuinely needed. If irritation occurs at any point, follow the 72-Hour Barrier Reset above rather than pushing through.

This product must be introduced as the ONLY new product. Wait 14 days before adding anything else. Retinization note: the initial adjustment period (flaking, mild redness) is temporary — reducing frequency, not stopping entirely, is the correct response if it's manageable but uncomfortable.

Antioxidant pollution defense: the included Vitamin E (Tocopheryl Acetate/Tocopherol) provides modest antioxidant support, helpful given Mauritius's July-November sugar cane burning season increases in airborne particulates — though this product's primary job is turnover, not pollution defense, so don't rely on it alone for that.

Decision point, end of Week 2: any persistent redness or burning? YES → stay at Week 1-2 frequency for 2 more weeks. NO → proceed to Week 3.