+ PLANT CALLUS VESICLESand many more lab-grade ingredients
48 in a single pen
Hair & scalp serum · Roller pen, 15 mL
one pen
AOQ520·10 actives · 0% alcohol
A scalp and root serum in a roller pen — 23.75% actives from ten, no alcohol, 4–5 clicks morning and night, for hair that looks fuller.
Early-bird price until 31 Dec 2026 · Pre-order · first lot ships early January 2027
Free delivery in Thailand · 2–3 working days · PromptPay · card · Apple Pay · Counts toward Nº 07
- Thai FDA notified
- GHPs · HACCP facility
- Alcohol-free
- Every ingredient published
- With physicians, researchers and pharmacists
Ten actives
Redensyl · Capixyl · Procapil · AnaGain · Capilia Longa · Cabelludin · ProliCell Malva · Stimucap SC · CG-Copper Peptide · AdenoSphere
Free from: ethanol · fragrance · essential oils · menthol · dye
How to use
- Press to release the serum — at least 4–5 clicks per use, more for larger areas
- With hair dry or slightly damp, glide the roller tip gently over the areas you want to care for. Leave in
- Use twice a day, morning and evening. We suggest at least 4–6 months of steady use · Can be used alongside U-TURN
Who it’s for
- Anyone who wants targeted scalp care, morning and night
- Sensitive scalps that react to fragrance or alcohol
- U-TURN users who want to care from the outside too
This product is Cosmetic · Ethanol-free · Fragrance-free · Menthol-free · Dye-free · Roller pen
01
One press. A measured dose.
The metal roller lays serum straight onto the scalp. No mess, no washing your hands.
02
10 actives · 0 alcohol
Chosen after reviewing 28 serums on the market. No ethanol, fragrance, essential oils, menthol or dye.
03
Morning, and before bed.
Light, fast-absorbing, non-sticky. Keep going for 4–6 months. Works alongside U-TURN.
The serum
10 actives. 0 alcohol.
Chosen from an evidence review of scalp serums, carried in a light texture with nothing a sensitive scalp doesn’t want.
- 0actives
- 0% alcohol
- 0clicks · AM & PM
- 0mL · about 2 months
Left out
Five things we don’t use
EthanolFragranceEssential oilsMentholDye
A sensitive scalp usually reacts to these before anything else, so the formula began with what to leave out. Every reason →
All ten actives10
Cosmetic — conditions scalp and hair; no medical effect · Active descriptions from raw-material suppliers, not studies of this product · Notification no. 74-1-6900030861
ONE PEN · every percentage
Actives in total0%in one pen
You should know what you are paying for, so every active carries its real number. Tap the bar or swipe the cards.
Conditions scalp and roots · reduces breakage · hair looks fuller, with more body
Swipe through all 10
- Botanical01 / 10
3%
Redensyl®
“Like good soil, around every root”
- Nourishes roots
- Hair looks fuller
- Peptide02 / 10
3%
Capixyl™
“Like grout, holding each root firm”
- Firmer anchoring
- Less breakage
- Peptide03 / 10
3%
Procapil®
“Like an anchor, keeping hair in place”
- Stronger hair
- Less breakage
- Bio-active04 / 10
3%
Stimucap SC
“Like a shield against free radicals”
- Antioxidant
- Balanced scalp
- Peptide05 / 10
3%
CG-Copper Peptide
“Tiny copper the skin already knows”
- Conditions scalp
- Stronger hair
- Plant cell06 / 10
2%
Capilia Longa™
“Turmeric cells grown in a lab — clean, identical every lot”
- Denser-looking hair
- Less breakage
- Botanical07 / 10
2%
AnaGain™
“The energy of a sprout, at its strongest”
- Nourishes roots
- Hair looks fuller
- Peptide08 / 10
2%
Cabelludin
“A two-peptide team for the root”
- Nourishes roots
- Stronger hair
- Plant cell09 / 10
2%
ProliCell Malva
“A soft blanket for the scalp, from mallow”
- Soothing
- Hydrating
- Bio-active10 / 10
0.75%
AdenoSphere
“Tiny capsules releasing adenosine slowly”
- Nourishes roots
- Hair looks fuller
Concentrations per formula sheet AOQ520 (24 Sep 2026) · Card backs summarise each raw-material maker’s documentation, not studies of ONE PEN · ONE PEN is a cosmetic that conditions scalp and hair; no medical effect · “Breakage” means hair snapping from combing and styling.
ONE PEN · The notes
Ten actives, in five layers
Tap a layer to see what is inside
- 10
- actives
- 48
- INCI
- 0%
- alcohol
- 15
- mL
-
Short amino-acid chains, designed for the scalp
-
Plant cells grown in the lab — pure, consistent, no field harvest
-
From larch wood, green tea and pea sprouts
-
Adenosine wrapped in lecithin, and glutathione bound to a fatty acid
-
A light, hydrating water base that sinks in fast — 0% alcohol
- NiacinamideVitamin B3
- PanthenolPro-vitamin B5
- EctoinSkin conditioning
- HyaluronateHydration
Cosmetic — conditions scalp and hair; no medical effect · Origins from the raw-material suppliers
How to use
Four moves, under a minute
- 01
Part
On a dry or towel-dried scalp, part the hair where you want to care for
-
024–5 clicks
Press the end until serum reaches the roller. More clicks for a larger area
- 03
Roll gently
Glide the metal roller along the part for a thin, even layer
- 04
Morning and bedtime
Leave in. Keep going for at least 4–6 months
What to expect
What the first months look like
Not a promise about results — what happens to your routine in each stretch, and where to pause and think.
- Day one
Patch-test, then keep it in sight
Roll a small area first. Then leave ONE PEN by the bed or next to the hairdryer — what you can see is what you use.
- Week 1
Make it a habit
Morning after styling, night after washing your face: part the hair, 4–5 clicks, roll gently, leave in. Under a minute.
- Months 1–2
The first pen runs low
One 15 mL pen lasts about 1–2 months. When a press gives less, order the next — every pen counts toward Nº 07.
- Months 3–4
Keep going, watch the scalp
The stretch where consistency matters most. If it stings, itches or irritates, stop, rinse, and tell us through Hari or LINE.
- Months 4–6
Assess
The period suggested on the box. Retake the 1-minute hair check, and if hair loss still worries you, see a specialist to find the cause.
Details
What it does
- 23.75% actives — ten peptides, plant-cell and botanical actives, every concentration published
- Conditions scalp and roots, strong hair from root to tip
- Reduces breakage from combing and styling; hair looks fuller, with more body
- A comfortable, hydrated scalp · no ethanol, fragrance, essential oils, menthol or dye
- Light, fast-absorbing, non-sticky · a measured dose with one press
How to use
- Press to release the serum — at least 4–5 clicks per use, more for larger areas
- With hair dry or slightly damp, glide the roller tip gently over the areas you want to care for. Leave in
- Use twice a day, morning and evening. We suggest at least 4–6 months of steady use · Can be used alongside U-TURN
Ten actives
| Active | What it is |
|---|---|
| Redensyl | Larch extract complex (DHQG, EGCG2) |
| Capixyl | Acetyl tetrapeptide-3 + red clover (Trifolium pratense) extract |
| Procapil | Biotinoyl tripeptide-1, apigenin, oleanolic acid |
| AnaGain | Pea sprout extract |
| Capilia Longa | Curcuma longa callus conditioned media |
| Cabelludin | Scalp-conditioning peptide complex |
| ProliCell Malva | Malva sylvestris callus extract |
| Stimucap SC | Botanical scalp complex |
| CG-Copper Peptide | Copper tripeptide-1 |
| AdenoSphere | Encapsulated adenosine |
Cosmetic — conditions scalp and hair; no medical effect · Ingredient descriptions from raw-material suppliers, not studies of this product
Full ingredient list (INCI)
Per the manufacturer’s formula sheet — the list on the box is the reference.
Warnings
- External use only. Avoid the eye area
- Read and follow the directions carefully
- If you notice any unusual reaction, stop use and ask a doctor or pharmacist
- Patch-test on a small area before first use
- Store away from heat, sunlight and children · Use within 3 months of opening
Q&A · 8 questions
ONE PEN, answered
The questions we hear most, answered from the real label.
-
01How is ONE PEN different from other scalp serums?
23.75% actives — and every percentage published
We reviewed the evidence behind 28 scalp serums on the market and brought ten actives — 23.75% in total (Redensyl, Capixyl, Procapil, Stimucap SC and CG-Copper Peptide at 3% each; Capilia Longa, AnaGain, Cabelludin and ProliCell Malva at 2%; AdenoSphere 0.75%) — into one formula: four peptides, two plant-cell technologies, botanical extracts and an encapsulated active — with no ethanol, fragrance, essential oils, menthol or dye. Then we put it in a roller pen that gives a measured dose with one press.
-
02Why a roller pen?
The serum reaches the scalp — not your hair ends or your palm
Droppers tend to run down the hair or onto your fingers. The metal roller tip of ONE PEN touches the scalp directly and spreads a thin, even layer. Every click gives the same amount, it fits in a bag, and there is nothing to wash off your hands.
-
03How do I get the most from it?
Part, 4–5 clicks, roll gently, leave in
Use on a dry or towel-dried scalp. Part the hair where you want to care for, press 4–5 clicks (more for a larger area) and roll the tip gently across. Morning and bedtime, for at least 4–6 months — consistency matters more than quantity.
-
04Will it feel sticky, greasy or flatten my hair?
No — light, fast-absorbing, ready to style
The formula is water-based, with no silicones or heavy oils. It sinks into the scalp within minutes and leaves no film on the hair, so it fits both a morning before work and a bedtime routine.
-
05Why no alcohol, menthol or fragrance?
Because a scalp needs care, not a tingle
Ethanol dries fast but dries the scalp out with daily use. Menthol’s cooling feels like it is working, but the feeling comes from stimulated nerve endings. Fragrance is the most common cause of contact allergy in cosmetics. ONE PEN has none of them, so it stays comfortable twice a day.
-
06I have a sensitive scalp — can I use it?
The formula started with you in mind
We removed the five things a sensitive scalp usually reacts to first, and built the base on glycerin, betaine, hyaluronate, panthenol and ectoin. Patch-test a small area before first use and stop if anything feels wrong — Hari and LINE @medology are always there.
-
07How long does one pen last?
15 mL lasts about 1–2 months
Used morning and bedtime as directed, one pen lasts about 1–2 months. The launch price is ฿990 until 31 December 2026 (regularly ฿1,200) — roughly ฿17–33 a day. Every pen counts toward Nº 07 · Use within three months of opening.
-
08Can I use it with U-TURN, and when does it ship?
Yes — the first lot ships in early January 2027
ONE PEN conditions the scalp from the outside; U-TURN works from the inside through nutrition — they sit together naturally. ONE PEN is open for pre-order, with free delivery across Thailand · Thai FDA notification 74-1-6900030861 · ONE PEN is a cosmetic that conditions scalp and hair; it has no medical effect.
Pair withU-TURNEvery milligram, considered. Made by Cosmed Innovation Co., Ltd., Samut Sakhon · Thai FDA cosmetic notification no. 74-1-6900030861 · Distributed by Rodsaniyom Dee Kern Keed Co., Ltd.