Cos De BAHA Retinol 2.5% Serum — at 2.5%, this is not a beginner’s retinol. Cos De BAHA’s Retinol 2.5% Serum is aimed at people who have already worked their way up through lower strengths and want to go further on fine lines, texture and tone.
Retinol is the single best-evidenced topical ingredient for skin ageing. It also has the steepest adjustment period.
Expect at first
Dryness, some flaking, possibly a purge of existing congestion in the first month. This is normal and it passes.
How to use Cos De BAHA Retinol 2.5% Serum
Night only, on clean dry skin, starting twice weekly and building slowly. Buffer with moisturiser if needed. Daily sunscreen is mandatory — retinol increases sun sensitivity.
Do not use
While pregnant or breastfeeding.
What is in it
Retinol
What separates a good retinol product from a harsh one is rarely the percentage — it is the base it sits in and how the retinol is stabilised. Encapsulated and buffered formulas release the active more gradually, which lowers irritation without lowering the eventual result. That matters most around the eyes and on skin that has reacted badly to retinoids before. Used at night, consistently, retinol remains the most reliable anti-ageing step available without a prescription. Background reading on retinol if you want the chemistry behind it.
What to use it with
Seal this in with a moisturiser and apply it to skin that is still damp from a toner — both steps make a measurable difference to how much of the serum stays where you put it. From the rest of our range, SKIN1004 Madagascar Centella Probio-Cica Enrich Cream and Beauty of Joseon Green Plum Aha Bubble Toner are sensible companions, and both are stocked with the same cash-on-delivery terms.
Where it fits in your routine
A serum goes on after cleansing and toning, while skin is still slightly damp, and before anything heavier. That order matters more than people expect — the thinnest, most concentrated layer needs direct contact with skin, not a film of moisturiser in the way. Give it thirty seconds to absorb, then seal it in with a cream. If you are using more than one serum, the lighter one goes first.
Before you start
This is a night product. Start twice a week, build up slowly, and stop increasing the moment skin starts to feel tight rather than dry. Sunscreen the following morning is not optional. Do not use retinoids while pregnant or breastfeeding.
Common questions
Is Cos De BAHA Retinol 2.5% Serum authentic?
Yes. Euros Belle stocks sealed, unopened units sourced through the brand’s own distribution, and we do not sell testers, decants or refilled packaging. Every order is checked before it leaves us, and you are welcome to inspect the seal at the door before paying.
Can I pay cash on delivery?
Cash on delivery is the only payment method we offer — there is nothing to pay in advance and no card details to enter anywhere. You pay the delivery agent when the parcel reaches you. Inside Dhaka delivery is ৳70 and takes one to two days; outside Dhaka it is ৳130 and takes three to four.
How long before I see a difference?
Longer than most marketing suggests. Pigment and firmness respond over eight to twelve weeks of consistent use, not days, and stopping and restarting resets that clock. Hydration and comfort improve much sooner — often within the first week.
Can I use this with my other products?
Not on the same night as another strong active. Keep retinoids and exfoliating acids on alternate evenings until you know how your skin responds to each. Niacinamide, hyaluronic acid, panthenol and ceramides layer with this without any conflict.
Will it suit my skin type?
Most skin types tolerate it, though anyone with reactive or recently over-exfoliated skin should introduce it slowly. If your barrier is currently compromised — stinging, tightness, unusual redness — repair that first with something simple before adding anything active.
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