Peptide

Acetyl Tetrapeptide-3

Also known as

Capixyl peptide · acetyl tetrapeptide-3 hair

Community talk. May contain inaccuracies. Not medical advice. Not a protocol. Not for human or animal use.

What it is

Cosmetic hair peptide	A peptide found in scalp, hair and lash products. People usually discuss it inside Capixyl or multi-ingredient serums.
Capixyl blend	Capixyl combines this peptide with red-clover extract. A serum's results do not show what the peptide alone does.

Notes

Acetyl Tetrapeptide-3 is a cosmetic peptide found in hair, scalp and lash products. Hair-loss communities usually discuss it inside Capixyl or multi-ingredient serums, hoping for less shedding and fuller hair. Reports range from cosmetic thickening and perceived growth to irritation or no benefit.

Capixyl contains more than this peptide. Acetyl Tetrapeptide-3 is one ingredient; Capixyl combines it with red-clover extract rich in biochanin A. The manufacturer promotes support for hair anchoring and growth. Those blend claims do not show that the peptide alone blocks hair-loss hormones or regrows hair. Lucas Meyer Cosmetics: Capixyl ingredient identity (Official context · Accessed 2026-09-30)

Serum experiences belong to the whole formula. The Ordinary reports involve caffeine, botanical extracts and other peptide complexes alongside Capixyl. A shampoo, scalp lotion and lash cosmetic can share an ingredient while delivering different exposures. Older organ-targeting bioregulator stories do not establish a whole-body effect for this cosmetic. The Ordinary hair serum: four-month personal review (Personal report · Accessed 2026-09-30)

Source context — Lucas Meyer Cosmetics: Capixyl ingredient identity: Manufacturer commercial claims. Confirms blend identity, not isolated-peptide efficacy, systemic kinetics or a safety assurance. Protected technical documents not accessed.

Source context — The Ordinary hair serum: four-month personal review: Anonymous multi-active serum report, no before/after photographs; wash frequency affects perceived shedding. The author's two early sensations and later improvement are one account, not corroboration.

What people notice

Less shedding	One reviewer noticed less hair fall by week three but remained unsure about new growth. Another reported less shedding with minimal gains in thinning areas.
Fuller-looking hair	One user saw denser-looking hair the next morning without feeling that hair loss had stopped. Other accounts report little benefit or no growth.

Notes

Less shedding does not necessarily mean new growth. One four-month reviewer reported markedly less hair fall by week three, while remaining unsure about new growth. They thought length increased faster, using haircut history rather than photographs. Their changing wash intervals also affected how much shedding they noticed. The Ordinary hair serum: four-month personal review (Personal report · Accessed 2026-09-30)

Less shedding and little regrowth can coexist. In an October 2022 Looksmax update, chigoha described two months with a Redensyl, Capixyl and Procapil serum: less shedding, slightly thicker side hair, but minimal gains in thinning areas. Repeated quotations of that post are one account. Redensyl, Capixyl and Procapil serum: two-month update (Community discussion · Accessed 2026-09-30)

Fuller-looking hair can be a styling effect. A tressless contributor saw healthier, denser-looking hair the next morning but did not think the serum stopped hair loss. Another discussion includes a favorable shampoo account alongside sticky texture and no-growth reports. Appearance and lasting regrowth are different outcomes. The Ordinary serum: fuller appearance versus hair-loss response (Community discussion · Accessed 2026-09-30) · Capixyl and Procapil results: mismatched products and conflicting accounts (Community discussion · Accessed 2026-09-30)

Modest benefit can still feel poor value. A self-described former cosmetic chemist reported only a small noticeable improvement with a 5% Capixyl serum after extensive testing and considered it overpriced. Their credentials and concentration explanation are unverified; the account does not establish a minimum effective peptide percentage. Scalp serum discussion by a self-described former cosmetic chemist (Community discussion · Accessed 2026-09-30)

Source context — Redensyl, Capixyl and Procapil serum: two-month update: One anonymous blended-serum account. Date of update is not implied start date; user's stated two months retained. Other replies concern Redensyl, oils and alopecia areata and are not AT3 evidence.

Source context — The Ordinary serum: fuller appearance versus hair-loss response: Deleted OP identity but text readable; commenter experiences and opinions are separate. No isolated ingredient or verified hair counts.

Source context — Capixyl and Procapil results: mismatched products and conflicting accounts: Do not assign Procapil-only irritation to acetyl tetrapeptide-3. The positive shampoo composition is commenter-reported; affiliations not established. No dose or duration for these replies.

Source context — Scalp serum discussion by a self-described former cosmetic chemist: Credentials, product concentrations and outcomes unverified. Brand advocacy challenged in replies; author denies ad intent. Proposed reduced frequency is not a completed follow-up or proven maintenance plan.

Doses people talk about

Serum application	One reviewer used about three drops per parting, a little over half a pipette per application, around four nights weekly. Other accounts describe once or twice daily use.
3% or 5% Capixyl	These are reported concentrations of the blend in finished products, not pure-peptide percentages or milligrams.
1.5–2 mL nightly lotion	One user reported this daily lotion volume with 5% Capixyl, 5% Procapil and other ingredients. The pure-peptide amount was unstated.

Notes

Reported routines range from four nights weekly to twice daily. The four-month reviewer used roughly three drops per parting, a little over half a pipette per application, around four nights weekly. Another thread's author used serum morning and night; a reply preferred once daily. Pipette size and area covered were not standardized. The Ordinary hair serum: four-month personal review (Personal report · Accessed 2026-09-30) · The Ordinary serum: fuller appearance versus hair-loss response (Community discussion · Accessed 2026-09-30)

3% and 5% refer to Capixyl blend content. A Haircross user transcribed 3.0% weight per volume (w/v) each of Capixyl, Redensyl, Procapil and Anagain, plus 2.0% w/v Baicapil. Other users discuss 5% Capixyl serums. These are product-level claims, not that percentage of pure peptide; peptide quantity and component ratios remain unstated. Haircross serum: reported blend percentages and concern about switching (Community discussion · Accessed 2026-09-30) · Scalp serum discussion by a self-described former cosmetic chemist (Community discussion · Accessed 2026-09-30)

1.5–2 mL is one lotion's application amount. AnnaMurr describes that volume and actual nightly use of a multi-active lotion reported as 5% Capixyl and 5% Procapil. Once-nightly use makes the stated application amount the daily lotion total; it gives no pure-peptide milligrams. AnnaMurr: Cosmo Capixyl+ lotion review (Personal report · Accessed 2026-09-30)

Source context — Haircross serum: reported blend percentages and concern about switching: Ingredient percentages are a user's label transcription, not independently tested amounts. This is a question, not a successful Haircross outcome; no application volume or frequency established.

Source context — AnnaMurr: Cosmo Capixyl+ lotion review: Russian body read and paraphrased in English; product composition not independently confirmed. Strong favorable review with other treatments and brand advocacy; photographs not visually validated. No component ratio/pure peptide amount. Author denies commissioned review in later comments.

Half-life, onset & duration

Felt onset	Next-morning fullness and less shedding by week three come from different accounts. Neither establishes when the peptide starts changing follicles.
Felt duration	The accounts do not establish how long one application helps or whether reduced shedding lasts after stopping.
Half-life	No measured human half-life after scalp application is established in the saved record.

Notes

Next-day appearance and week-three shedding are separate landmarks. The fuller-look account describes the morning after application. The four-month reviewer noticed early next-day scalp tingling and later less shedding by week three. Neither establishes when this peptide starts changing follicles. The Ordinary serum: fuller appearance versus hair-loss response (Community discussion · Accessed 2026-09-30) · The Ordinary hair serum: four-month personal review (Personal report · Accessed 2026-09-30)

One application's benefit duration is unknown. Reports cover next-morning appearance or observations during repeated use. They do not establish an hours-long active window or how long reduced shedding persists after stopping. The four-month reviewer's tingling diminished on the second use and then did not recur. The Ordinary serum: fuller appearance versus hair-loss response (Community discussion · Accessed 2026-09-30) · The Ordinary hair serum: four-month personal review (Personal report · Accessed 2026-09-30)

Permanent gains are an unsupported promise. A Looksmax poster assumed serum gains would remain permanently before later reporting their experience. The thread contains no stop-and-follow-up evidence establishing that assumption. Redensyl, Capixyl and Procapil serum: two-month update (Community discussion · Accessed 2026-09-30)

No measured human half-life in these discussions. Claims that short peptides disappear rapidly come from broader peptide lore. They do not measure how long intact Acetyl Tetrapeptide-3 remains in a person after scalp application. Daily use and months-long hair observations cannot fill that gap.

Cycles people discuss

Continued application	Users describe three to four months of use. One planned to reduce daily use to every second or third day, but had not reported maintenance results.
Breaks	The topical accounts establish no agreed break length. Older 10–20-day seasonal bioregulator courses do not establish a Capixyl-serum calendar.

Notes

Users describe months of continued application. Accounts include roughly four months of use and a newer contributor's three months daily. The newer contributor planned to reduce frequency to every second or third day while also using dandruff shampoo, massage and red light; maintenance results were not reported. The Ordinary hair serum: four-month personal review (Personal report · Accessed 2026-09-30) · Scalp serum discussion by a self-described former cosmetic chemist (Community discussion · Accessed 2026-09-30)

10–20-day seasonal courses are bioregulator lore. Older notes mention short courses repeated a few times yearly and weeks-on/weeks-off patterns. Those are not a demonstrated Capixyl-serum calendar. No agreed break length or need to cycle emerges from the inspected topical accounts.

Stacks

Multi-ingredient serums	Capixyl appears with Redensyl, Procapil, other peptide complexes, botanicals and caffeine. Results belong to the whole formula.
Other hair treatments	Some users also used finasteride, dermarolling, Minoxin or intermittent aminexil. Those accounts cannot isolate this peptide's contribution.

Notes

Blend versus bioregulator stacks: Older notes describe multi-bioregulator combinations by organ system; that is separate from the cosmetic product here. Capixyl includes red-clover extract, and reviewed finished-serum accounts include other peptide/botanical complexes and caffeine, preventing single-ingredient attribution. [community]

Opening text lines 21–27: morning/night serum, finasteride and dermarolling; peebaby lines 50–55: fuller next-day appearance, no perceived prevention of loss, excess greasiness; fraybentosss lines 64–70: once-daily opinion. The Ordinary serum: fuller appearance versus hair-loss response (Community discussion · Accessed 2026-09-30)

September 10, 2026 body lines 79–109: reported 5% Capixyl, 5% Procapil and other actives; usage paragraph says ~1.5–2 mL, actual once-nightly use over three months, morning Minoxin plus intermittent aminexil; new hairs noticed around month one. Lines 93–101: waterlike, odorless, loses volume. AnnaMurr: Cosmo Capixyl+ lotion review (Personal report · Accessed 2026-09-30)

Watch for

Scalp discomfort	Early tingling faded for one reviewer; another commenter washed the serum off and stopped. Tingling does not demonstrate hair growth.
Sticky or greasy hair	Texture varies by product and amount; users describe greasiness, stickiness and changes that clear by morning.
Product and route limits	Allergy and uncertain ingredients remain concerns. Scalp-serum reports establish neither eye-area tolerability nor an injectable dose.

Notes

Tingling does not demonstrate growth. A separate commenter washed the serum off after an uncomfortable scalp sensation and never resumed it. The Ordinary's directions advise patch testing, use on unbroken skin, and discontinuation with medical advice if irritation occurs. Scalp-serum reports do not establish lash or eye-area tolerability. The Ordinary hair serum: four-month personal review (Personal report · Accessed 2026-09-30) · The Ordinary: ingredient list and product safety directions (Official context · Accessed 2026-09-30)

Texture can determine whether people keep using it. The four-month reviewer found temporary greasiness that cleared by morning. The next-day-density user found excess application greasy. A newer serum commenter described wet stickiness that dried comfortably. These product differences matter even when ingredient lists sound similar. The Ordinary hair serum: four-month personal review (Personal report · Accessed 2026-09-30) · The Ordinary serum: fuller appearance versus hair-loss response (Community discussion · Accessed 2026-09-30) · Scalp serum discussion by a self-described former cosmetic chemist (Community discussion · Accessed 2026-09-30)

Ingredient and safety uncertainty remain. Unknown impurities, allergy and poorly characterized long-term gray-market use remain cautions. Cosmetic discussion supplies no validated injectable route; inherited injection-reaction notes do not establish one for this peptide. Severe allergy or serious chest, neurological, blood-pressure or glucose symptoms require medical care. Finished-product storage and handling are product-specific.

Source context — The Ordinary: ingredient list and product safety directions: Commercial finished-product label, formulation may vary by time/region. Product-label frequency is separately identified context, not evidence of a community dose or safe injectable route.

Full notes

What the peptide and the blend are

Capixyl contains more than this peptide. Acetyl Tetrapeptide-3 is one ingredient; Capixyl combines it with red-clover extract rich in biochanin A. The manufacturer promotes support for hair anchoring and growth. Those blend claims do not show that the peptide alone blocks hair-loss hormones or regrows hair. Official context
Serum experiences belong to the whole formula. The Ordinary reports involve caffeine, botanical extracts and other peptide complexes alongside Capixyl. A shampoo, scalp lotion and lash cosmetic can share an ingredient while delivering different exposures. Older organ-targeting bioregulator stories do not establish a whole-body effect for this cosmetic. Personal report Community

What people hope to notice

Less shedding does not necessarily mean new growth. One four-month reviewer reported markedly less hair fall by week three, while remaining unsure about new growth. They thought length increased faster, using haircut history rather than photographs. Their changing wash intervals also affected how much shedding they noticed. Personal report
Fuller-looking hair can be a styling effect. A tressless contributor saw healthier, denser-looking hair the next morning but did not think the serum stopped hair loss. Another discussion includes a favorable shampoo account alongside sticky texture and no-growth reports. Appearance and lasting regrowth are different outcomes. Reddit · tressless Reddit · tressless

Doses and amounts people discuss

Reported routines range from four nights weekly to twice daily. The four-month reviewer used roughly three drops per parting, a little over half a pipette per application, around four nights weekly. Another thread's author used serum morning and night; a reply preferred once daily. Pipette size and area covered were not standardized. Personal report Reddit · tressless
3% and 5% refer to Capixyl blend content. A Haircross user transcribed 3.0% weight per volume (w/v) each of Capixyl, Redensyl, Procapil and Anagain, plus 2.0% w/v Baicapil. Other users discuss 5% Capixyl serums. These are product-level claims, not that percentage of pure peptide; peptide quantity and component ratios remain unstated. Reddit · tressless Reddit · tressless
1.5–2 mL is one lotion's application amount. AnnaMurr describes that volume and actual nightly use of a multi-active lotion reported as 5% Capixyl and 5% Procapil. Once-nightly use makes the stated application amount the daily lotion total; it gives no pure-peptide milligrams. Personal report
The broader concentration range is not a dose chart. Older cosmetic discussion spans parts per million to low single-digit percentages without identifying every formulation. It cannot settle an isolated-peptide amount, and cosmetic concentrations cannot supply an injection dose. Community

Half-life

No measured human half-life in these discussions. Claims that short peptides disappear rapidly come from broader peptide lore. They do not measure how long intact Acetyl Tetrapeptide-3 remains in a person after scalp application. Daily use and months-long hair observations cannot fill that gap. Community

When people first notice something

Next-day appearance and week-three shedding are separate landmarks. The fuller-look account describes the morning after application. The four-month reviewer noticed early next-day scalp tingling and later less shedding by week three. Neither establishes when this peptide starts changing follicles. Reddit · tressless Personal report
Fast growth claims need their context. A 2026 commenter reported tiny hairline hairs after about a week and a half with a Capixyl serum. That short self-observation, without controlled photographs or isolated ingredients, is not a reliable regrowth timetable. Reddit · tressless

How long a noticed change lasts

One application's benefit duration is unknown. Reports cover next-morning appearance or observations during repeated use. They do not establish an hours-long active window or how long reduced shedding persists after stopping. The four-month reviewer's tingling diminished on the second use and then did not recur. Reddit · tressless Personal report
Permanent gains are an unsupported promise. A Looksmax poster assumed serum gains would remain permanently before later reporting their experience. The thread contains no stop-and-follow-up evidence establishing that assumption. Looksmax.org

Courses, continued use and breaks

Users describe months of continued application. Accounts include roughly four months of use and a newer contributor's three months daily. The newer contributor planned to reduce frequency to every second or third day while also using dandruff shampoo, massage and red light; maintenance results were not reported. Personal report Reddit · tressless
10–20-day seasonal courses are bioregulator lore. Older notes mention short courses repeated a few times yearly and weeks-on/weeks-off patterns. Those are not a demonstrated Capixyl-serum calendar. No agreed break length or need to cycle emerges from the inspected topical accounts. Community

Cautions and evidence limits

Tingling does not demonstrate growth. A separate commenter washed the serum off after an uncomfortable scalp sensation and never resumed it. The Ordinary's directions advise patch testing, use on unbroken skin, and discontinuation with medical advice if irritation occurs. Scalp-serum reports do not establish lash or eye-area tolerability. Personal report Official context
Small combination studies cannot prove peptide equivalence. A 2020 trial studied 32 people for 24 weeks using a biochanin A, peptide and ginseng combination, 1 mL per application twice daily: 2 mL/day. Hair counts improved without a significant difference versus 3% minoxidil. That small comparison does not prove equivalence or isolate this peptide. Official context
Ingredient and safety uncertainty remain. Unknown impurities, allergy and poorly characterized long-term gray-market use remain cautions. Cosmetic discussion supplies no validated injectable route; inherited injection-reaction notes do not establish one for this peptide. Severe allergy or serious chest, neurological, blood-pressure or glucose symptoms require medical care. Finished-product storage and handling are product-specific. Community

What the reports add

Less shedding and little regrowth can coexist. In an October 2022 Looksmax update, chigoha described two months with a Redensyl, Capixyl and Procapil serum: less shedding, slightly thicker side hair, but minimal gains in thinning areas. Repeated quotations of that post are one account. Looksmax.org
Replacing another treatment changes the interpretation. HairLossTalk user anik reported no benefit and increased shedding over three months after stopping finasteride while starting Capixyl. The simultaneous switch prevents blaming Capixyl alone; the repeated paragraph is the same report. HairLossTalk
Texture can determine whether people keep using it. The four-month reviewer found temporary greasiness that cleared by morning. The next-day-density user found excess application greasy. A newer serum commenter described wet stickiness that dried comfortably. These product differences matter even when ingredient lists sound similar. Personal report Reddit · tressless Reddit · tressless
Modest benefit can still feel poor value. A self-described former cosmetic chemist reported only a small noticeable improvement with a 5% Capixyl serum after extensive testing and considered it overpriced. Their credentials and concentration explanation are unverified; the account does not establish a minimum effective peptide percentage. Reddit · tressless
A negative product story can concern a different ingredient. In the Capixyl/Procapil thread, one detailed irritation story actually concerns a Procapil shampoo. Another responder reported no growth and stickiness without naming the formula, while a third praised a Capixyl-containing shampoo. These cannot become one verdict about isolated Acetyl Tetrapeptide-3. Reddit · tressless