The Ordinary Multi-Peptide Serum for Hair Density: Reviews and Evidence
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Many reviews of The Ordinary Multi-Peptide Serum for Hair Density describe less shedding, but no published trial has tested the finished serum. Its ingredients, including Redensyl, Procapil, acetyl tetrapeptide-3 and red clover, have small studies in other formulas, and some of those studies are industry-linked. It's a cosmetic option for early thinning. It is not a proven regrowth treatment. Evidence: Limited.
We haven't tested this serum. This is an ingredient-and-evidence breakdown. Ingredients are as listed on The Ordinary's US product page, checked on October 22, 2026. The brand says formulas vary by time and region, so check your label. For how peptides are classified in general, see our peptide ingredients guide, ranked by evidence. For the wider hair-peptide evidence, see our guide to peptides for hair growth.
Key takeaways
- The Ordinary Multi-Peptide Serum for Hair Density contains no copper peptide, and the brand doesn't disclose any ingredient concentrations (The Ordinary).
- A 2013 placebo-controlled trial in 30 volunteers found that a red clover plus "biomimetic peptide" ingredient raised the anagen/telogen ratio 46% over 4 months, while placebo fell 33% (Loing et al., 2013).
- A 2020 triple-blind trial in 32 people found that a blend with acetyl tetrapeptide-3 performed similarly to 3% minoxidil at 24 weeks. That blend isn't this serum (Lueangarun & Panchaprateep, 2020).
- A 2025 review of Redensyl, Procapil, Capixyl, Baicapil and AnaGain called the results promising but flagged small samples, undisclosed alopecia types and conflicts of interest (Bikash, 2025).
- Ingredient trials ran 60 days to 6 months (Merja et al., 2024; Khoso & Fahim, 2024).
The Ordinary Multi-Peptide Serum for Hair Density reviews: does it work?
We don't know, because nobody has published a trial of the finished serum. Its ingredients have produced modest gains in small studies of other formulas. The best case is a reasonable cosmetic add-on for early thinning.
Three findings anchor the case for the ingredients. A red clover plus peptide ingredient beat placebo on hair-cycle measures in 30 people over 4 months (Loing et al., 2013). A Redensyl-containing lotion was tested against vehicle in 44 people with pattern hair loss (Katoulis et al., 2020). An acetyl tetrapeptide-3 blend matched 3% minoxidil in 32 people (Lueangarun & Panchaprateep, 2020).
A 2025 review read across 24 articles and technical files on these actives. Its verdict was that they "may find their use as an add-on therapy or as an alternative in patients not tolerating standard therapies" (Bikash, 2025). That is the most an independent source says about them.
Evidence: Limited.
What's in The Ordinary Multi-Peptide Serum for Hair Density (and what isn't)?
The serum is a water, propanediol and glycerin base carrying 5 branded ingredient complexes plus caffeine. INCI names are the standardized ingredient names printed on cosmetic labels.
The full INCI from the US product page is: Aqua (Water), Propanediol, Butylene Glycol, Glycerin, Caffeine, Biotinoyl Tripeptide-1, Acetyl Tetrapeptide-3, Larix Europaea Wood Extract, Pisum Sativum Extract, Scutellaria Baicalensis Root Extract, Triticum Vulgare Germ Extract, Glycine Soja Germ Extract, Trifolium Pratense Flower Extract, Camellia Sinensis Leaf Extract, Apigenin, Oleanolic Acid, Arginine, Glycine, Calcium Gluconate, Zinc Chloride, Lactic Acid, Gluconolactone, Dextran, Maltodextrin, Hydroxyethylcellulose, Xanthan Gum, Pentylene Glycol, Dimethyl Isosorbide, Polysorbate 20, PPG-26-Buteth-26, PEG-40 Hydrogenated Castor Oil, Trisodium Ethylenediamine Disuccinate, Sodium Metabisulfite, Sodium Benzoate, Phenoxyethanol, Chlorphenesin (The Ordinary).
The brand groups those ingredients into these complexes:
| Complex | What the brand says it contains | PubMed studies in our review |
|---|---|---|
| Redensyl | Sodium metabisulfite, European larch extract, glycine, zinc chloride, green tea extract | Yes, mostly in combinations |
| AnaGain | Pea sprout extract | Only inside multi-ingredient serums |
| Procapil | Apigenin, oleanolic acid, biotinoyl tripeptide-1 | Yes, mostly with PRP |
| Capixyl | Acetyl tetrapeptide-3 with red clover extract | Related blends only |
| Baicapil | Chinese skullcap with soy and wheat germ extracts | None found; named only in a review |
| Caffeine | "High-solubility" caffeine | None in our review |
The brand doesn't publish concentrations for any complex, so you can't match this serum's doses to the study doses.
It contains no copper peptide. If you want copper peptides for your face, our guide to copper peptides for skin covers that category. Copper-peptide hair data come mostly from lab work, such as AHK-Cu lengthening hair follicles in a dish (Pyo et al., 2007). A 2026 systematic review called human GHK-Cu trials "thin and fragmented" (Najafi et al., 2026). The full picture is in our copper peptides for hair evidence review and our AHK-Cu explainer.
What do the ingredient studies show?
The studies show small, positive changes for some ingredients, but almost always in other formulas, often with other treatments added, and often without a placebo. Two hair-cycle terms come up repeatedly. Anagen is the growing phase, and telogen is the resting phase before a hair sheds.
| Loing 2013 | 30 | 4 months | Daily topical red clover extract + unnamed peptide | Anagen +13%, telogen −29%, A/T ratio +46% vs placebo −33% |
| Katoulis 2020 | 44 randomized, 41 completed | 24 weeks | Redensyl + Sepicontrol A5 lotion, twice daily | Active group: 7.7% great, 73.1% moderate improvement, 19.2% stable |
| Lueangarun 2020 | 32 | 24 weeks | Biochanin A + acetyl tetrapeptide-3 + ginseng, 1 mL twice daily | Terminal hairs +8.3% vs +8.7% with 3% minoxidil, no significant difference |
| Khoso 2024 | 160 | 6 months | 5% Procapil twice daily + PRP vs PRP alone | Better dermatologist and satisfaction scores with Procapil (p < 0.05) |
| Tr 2023 | 54 men | 4 PRP sessions, 3 weeks apart | Procapil + PRP vs Redensyl, saw palmetto and biotin + PRP | Groups differed on AGA grading (P < 0.05); authors favored the Redensyl combination |
| Merja 2024 | 32 | 60 days | Serum with Redensyl, AnaGain, Procapil, Capilia longa, hyaluronic acid; 0.5 mL daily | Hair growth rate +10.52% at 30 days, +31.62% at 60 days |
| Patel 2025 | Not reported in abstract | 120 days | Redensyl + AnaGain + rosemary oil serum | Hair density +37.92%, hair fall −64.89% at Day 120 |
Loing 2013
Result: Anagen +13%, telogen −29%, A/T ratio +46% vs placebo −33%
Randomized, placebo-controlled, volunteers with recessing hair. The abstract does not name Capixyl or the peptide. The paper describes developing the ingredient. Funding not reported in the abstract.
Katoulis 2020
Result: Active group: 7.7% great, 73.1% moderate improvement, 19.2% stable
Single-blinded and vehicle-controlled in AGA. The abstract reports within-group changes but no active-vs-vehicle statistic. No significant adverse events. Funding not reported in the abstract.
Lueangarun 2020
Result: Terminal hairs +8.3% vs +8.7% with 3% minoxidil, no significant difference
Triple-blind randomized trial in mild to moderate AGA. No funding, and no conflicts declared.
Khoso 2024
Result: Better dermatologist and satisfaction scores with Procapil (p < 0.05)
Quasi-experimental (not randomized). Every participant received PRP injections, so there was no topical-only arm.
Tr 2023
Result: Groups differed on AGA grading (P < 0.05); authors favored the Redensyl combination
Randomized. Both arms had PRP, and there was no placebo arm. No competing interests declared.
Merja 2024
Result: Hair growth rate +10.52% at 30 days, +31.62% at 60 days
Uncontrolled safety and efficacy study, adults aged 18 to 45. No adverse events reported. Funding not reported in the abstract.
Patel 2025
Result: Hair density +37.92%, hair fall −64.89% at Day 120
Open-label, single-arm study in women. Funded by the product's maker, and one author is employed there.
None of these studies tested The Ordinary's serum. Concentrations in The Ordinary's formula are not disclosed.
Red clover plus peptide. This study is the closest match to the Capixyl pairing of acetyl tetrapeptide-3 and red clover, but the abstract names neither Capixyl nor the peptide (Loing et al., 2013). It's the only placebo-controlled result in this group with numbers for both arms.
Redensyl. The Redensyl lotion trial also contained a second patented complex, Sepicontrol A5, so you can't credit Redensyl alone (Katoulis et al., 2020). The other Redensyl data come from combinations with PRP (platelet-rich plasma injections), saw palmetto, biotin or rosemary (Tr et al., 2023; Patel et al., 2025).
Procapil and AnaGain. Procapil was tested at 5% alongside PRP (Khoso & Fahim, 2024). AnaGain appears only inside multi-ingredient serums.
Baicapil and caffeine. We found no PubMed study for either one alone in the sources we reviewed.
Evidence: Limited.
Are The Ordinary Multi-Peptide Serum for Hair Density reviews backed by a product trial?
No. We found no published trial of this finished serum, and the brand page makes a cosmetic claim about the appearance of thicker, denser hair rather than citing a product study.
Ingredient results don't transfer automatically, for 3 reasons:
- Different formulas and doses. The studies used their own blends at their own strengths, and The Ordinary doesn't disclose its concentrations.
- Add-on treatments. Two studies gave every participant PRP injections, so the topical's own effect is unclear (Khoso & Fahim, 2024; Tr et al., 2023).
- Unclear hair loss types. The 2025 review noted that many studies don't disclose which type of alopecia they treated (Bikash, 2025).
Funding matters too. The rosemary-Redensyl serum study was funded by its maker (Patel et al., 2025). The red clover paper describes developing the ingredient it tested (Loing et al., 2013). The 2025 review lists conflicts of interest as a recurring weakness across this literature. Penetration is another open question. No study we found measured how far these complexes get into the scalp, which is a general issue covered in do peptides absorb into skin.
Evidence: Limited.
How does The Ordinary hair serum compare with minoxidil?
No study has compared this serum with minoxidil. The only head-to-head we found tested a different peptide blend against 3% minoxidil. Both groups gained terminal hairs, and the difference between them wasn't significant.
Show data table
| Treatment | Increase in terminal hairs (%) |
|---|---|
| Biochanin A + acetyl tetrapeptide-3 + ginseng blend | 8.3% |
| 3% minoxidil solution | 8.7% |
In that trial, 32 adults with mild to moderate pattern hair loss applied 1 mL twice daily for 24 weeks. The blend caused no local reactions, while 1 person on minoxidil developed scalp eczema. The authors called for larger, longer studies (Lueangarun & Panchaprateep, 2020).
| Feature | The Ordinary Multi-Peptide Serum for Hair Density | Trial blend | |||
|---|---|---|---|---|---|
| Acetyl tetrapeptide-3 | Yes | Yes | |||
| Red clover (biochanin A source) | Red clover extract | Biochanin A | |||
| Ginseng | No | Yes | |||
| Redensyl | Procapil | Baicapil | AnaGain | Yes | No |
| Concentrations disclosed | No | Not in abstract | |||
| Tested against minoxidil | No | 3% solution |
Bottom line: The two formulas overlap on one ingredient, so the trial result can't stand in for The Ordinary's serum.
The 2025 review placed these actives as a possible add-on, or an alternative for people who can't tolerate standard therapy (Bikash, 2025). That's expert opinion. If you use minoxidil or any prescription treatment, talk to your dermatologist before changing anything.
Evidence: Limited.
What do The Ordinary Multi-Peptide Serum for Hair Density reviews say about results?
User reviews mostly describe less shedding first, then fine new hairs at the hairline after a couple of months. These reports are anecdotes, and several confounders make them hard to interpret.
The reader questions we see most often, in our own words:
- "Less hair in the shower but no new growth yet: is it working?" Reduced shedding is the most common positive report, often before any visible regrowth.
- "Are these baby hairs from the serum?" Many reviewers notice short hairs at the temples and hairline. Some were recovering from pregnancy, illness or thyroid problems, and no study we found separates the serum's effect from regrowth after those events.
- "Is it the serum or the massage?" Some users credit scalp massage plus serum, and some wonder whether the massage alone helped.
- "Why is my hair greasier?" Some users with fine hair find the serum tacky and wash more often. Others call it lightweight.
- "Do I have to keep using it?" Long-term users often say results fade if they stop.
Keep 3 limits in mind. Retail reviews are self-selected, and some are marked as gifted by the brand. Many people measure hair length, which reflects normal growth, not density, which is how many hairs you have. And none of these reports has a control group.
How long before you see results from The Ordinary hair density serum?
The brand publishes no trial-based timeline. Ingredient studies in other formulas measured results between 60 days and 6 months, so plan to give it at least a few months before judging.
When ingredient studies measured results (other formulas, not this serum)
- 30 daysFirst growth-rate check
Uncontrolled REGENDIL serum study: hair growth rate +10.52% (n=32).
- 60 daysEnd of the shortest study
Same study: growth rate +31.62%. No control group.
- 12 weeksMid-trial checkpoint
Redensyl lotion trial: median A/T ratio rose from 2.25 to 4.00.
- 4 monthsRed clover + peptide trial ends
A/T ratio +46% vs −33% with placebo (n=30).
- 120 daysRosemary-Redensyl serum study ends
Maker-funded, open-label. Density +37.92%.
- 24 weeksLongest topical-only RCTs end
Redensyl lotion trial and the acetyl tetrapeptide-3 vs 3% minoxidil trial.
- 6 monthsProcapil + PRP study ends
Better scores than PRP alone (n=160, not randomized).
Sources for the timeline: Merja et al., 2024; Katoulis et al., 2020; Loing et al., 2013; Patel et al., 2025; Lueangarun & Panchaprateep, 2020; Khoso & Fahim, 2024. Any shorter promise, such as "results in 8 weeks," comes from marketing or user anecdote, not a trial. For directions, follow the product label.
Evidence: Limited.
Which kind of hair loss is The Ordinary hair density serum for?
The ingredient trials mostly enrolled people with androgenetic alopecia (AGA), the genetic, hormone-sensitive form usually called pattern hair loss. Evidence for other types of hair loss is missing.
Two studies enrolled broader groups. One recruited adults with "hair fall complaints" (Merja et al., 2024), and another recruited women with self-reported thinning for a personalized kit (Bhardwaj et al., 2025). We found no study of these complexes in traction alopecia (loss from tight styling), postpartum shedding, or shedding after rapid weight loss. For thinning around menopause, see our menopause hair loss guide.
That includes GLP-1 medications. No study we found tested these ingredients for shedding while on semaglutide or tirzepatide. Our pages on Ozempic hair loss, tirzepatide hair loss and GLP-1 skin changes cover what is known. Raise shedding with your prescriber rather than changing your dose yourself.
Getting a diagnosis first is standard clinical practice, especially for sudden, patchy or itchy hair loss. The studies above didn't test that advice, but the type of hair loss decides which treatments make sense.
Evidence: Limited.
Does The Ordinary hair serum cause side effects like greasiness or itching?
The ingredient trials reported few problems, but they were small and short. User complaints center on residue and occasional scalp irritation.
The Redensyl lotion trial reported no significant adverse events over 24 weeks (Katoulis et al., 2020). The acetyl tetrapeptide-3 blend caused no local reactions (Lueangarun & Panchaprateep, 2020). Two serum studies reported no adverse events over 60 to 120 days (Merja et al., 2024; Patel et al., 2025).
Those findings don't cover this formula. The INCI includes polysorbate 20, PEG-40 hydrogenated castor oil and sodium metabisulfite, and no study we found tested scalp tolerance of this exact mix. One reviewer with seborrheic dermatitis reported itching after use. If you have a scalp condition, ask a dermatologist first. Pregnancy and breastfeeding data don't exist for this serum, so ask a clinician.
Evidence: Early / preliminary.
How does it compare with other hair growth serum trials?
Most hair-serum trials share the same weaknesses as the studies behind The Ordinary's ingredients: small samples, missing control groups and funding from the brand. One well-run trial of a different serum found no benefit at all.
| Study | Design | Result | Caveat |
|---|---|---|---|
| Arruda 2025 | Open-label, n=20, 6 months | Investigator ratings rose from 0.75 and 0.81 to 1.73 and 1.83; 85% reported improvement | No control group |
| Weir 2025 | Double-blind placebo-controlled, n=39 | Beat placebo at months 3 and 6 for volume, density and coverage | Funded in part by the maker |
| Bhardwaj 2025 | Uncontrolled, 38 enrolled, 27 completed, 24 weeks | Shedding fell 37.3% at 12 weeks and 32.4% at 24 weeks | Combined serums, shampoos and supplements |
| Mann 2026 | Single-arm, 20 evaluable | KGF serum: none achieved meaningful hair preservation during chemotherapy | Different use case |
The last row is a useful check. When a serum was tested against a clear, hard endpoint, it failed. Positive results in uncontrolled studies don't guarantee a product works.
Evidence: Limited.
Where the evidence stops
- No product trial. No published study tests The Ordinary's finished serum.
- No doses. Concentrations aren't disclosed, so study doses can't be matched.
- Baicapil and caffeine. We found no PubMed studies for either one alone.
- Capixyl attribution. The red clover trial doesn't name Capixyl or acetyl tetrapeptide-3.
- No 5% minoxidil comparison. The only head-to-head used 3%, and a different blend.
- No data for postpartum, traction or GLP-1-related shedding, for use alongside minoxidil, or for pregnancy.
FAQ
Does The Ordinary Multi-Peptide Serum for Hair Density actually work?
No published trial has tested the finished serum, so nobody can say how well it works. Some of its ingredients have small studies in other formulas, and a 2025 review called that evidence promising but limited by small samples, few comparisons with standard treatment and conflicts of interest.
How long does The Ordinary hair density serum take to show results?
The brand gives no trial-based timeline. Studies of its ingredients in other formulas ran from 60 days to 6 months, so judging the serum after a few weeks tells you little.
Is The Ordinary hair serum as good as minoxidil?
No study has compared this serum with minoxidil. In one 32-person trial, a different blend containing acetyl tetrapeptide-3 performed similarly to 3% minoxidil solution at 24 weeks, but that blend is not this product. Talk to a dermatologist before changing any hair loss treatment.
Does The Ordinary Multi-Peptide Serum for Hair Density contain copper peptides?
No. The ingredient list on The Ordinary's US product page contains no copper peptide. Copper-peptide evidence for hair is covered in our copper peptides for hair guide.
Can I use The Ordinary hair serum with minoxidil?
No study has tested this combination. Ask your dermatologist before layering scalp treatments.
Can it help hair shedding on Ozempic, Wegovy, Mounjaro or Zepbound?
No study we found tested these ingredients for shedding linked to GLP-1 medications or rapid weight loss. Don't change your medication on your own; raise hair shedding with your prescriber.
Why does my scalp feel greasy or itchy after using it?
Some users describe a tacky or greasy feel, especially on fine hair, and some report itching. The ingredient trials reported no significant adverse events, but they were small and short. If irritation persists, stop using it and see a dermatologist.
Is The Ordinary hair density serum safe during pregnancy or breastfeeding?
We found no pregnancy or breastfeeding data for this serum or its ingredient complexes. Ask a clinician before using it.
References
- The Ordinary. Multi-Peptide Serum for Hair Density, US product page (INCI, size, pH). theordinary.com. 2026. Brand page, checked October 22, 2026. https://theordinary.com/en-us/multi-peptide-serum-for-hair-density-hair-scalp-treatment-100434.html
- Loing E, et al. A new strategy to modulate alopecia using a combination of two specific and unique ingredients. J Cosmet Sci. 2013. Randomized placebo-controlled, n=30, 4 months; ingredient-development paper; funding not reported in abstract. https://pubmed.ncbi.nlm.nih.gov/23449130/
- Katoulis AC, et al. A randomized, single-blinded, vehicle-controlled study of a topical active blend in the treatment of androgenetic alopecia. Dermatol Ther. 2020. RCT, n=44 (41 completed), 24 weeks; funding not reported in abstract. https://pubmed.ncbi.nlm.nih.gov/32473084/
- Lueangarun S, Panchaprateep R. An Herbal Extract Combination (Biochanin A, Acetyl tetrapeptide-3, and Ginseng Extracts) versus 3% Minoxidil Solution for the Treatment of Androgenetic Alopecia: A 24-week, Prospective, Randomized, Triple-blind, Controlled Trial. J Clin Aesthet Dermatol. 2020. Triple-blind RCT, n=32, 24 weeks; no funding, no conflicts declared. https://pubmed.ncbi.nlm.nih.gov/33584955/
- Khoso H, Fahim M. COMPARISON OF PLATELET RICH THERAPY ALONE WITH PLATELET RICH THERAPY ALONG WITH DAILY TOPICAL 5% PROCAPIL APPLICATION FOR THE TREATMENT OF ANDROGENETIC ALOPECIA. J Ayub Med Coll Abbottabad. 2024. Quasi-experimental, n=160, 6 months. https://pubmed.ncbi.nlm.nih.gov/39609969/
- Tr P, et al. A Comparative Study of Topical Procapil With Platelet-Rich Plasma Therapy Versus Topical Redensyl, Saw Palmetto, and Biotin With Platelet-Rich Plasma Therapy in the Treatment of Androgenetic Alopecia. Cureus. 2023. RCT, n=54 men, 4 PRP sessions; no competing interests declared. https://pubmed.ncbi.nlm.nih.gov/37292551/
- Merja A, et al. Safety and efficacy of REGENDIL™ infused hair growth promoting product in adult human subject having hair fall complaints (alopecia). J Cosmet Dermatol. 2024. Uncontrolled, n=32, 60 days; funding not reported in abstract. https://pubmed.ncbi.nlm.nih.gov/38050644/
- Patel M, et al. A Clinical Evaluation of the Safety, Efficacy, and Tolerability of the Soulflower Rosemary Redensyl Hair Growth Serum, Tetragain™, in Healthy Female Subjects for the Treatment of Alopecia: Promoting Hair Growth and Reducing Gray Hair. Cureus. 2025. Open-label single-arm, n not reported in abstract, 120 days; funded by the product maker. https://pubmed.ncbi.nlm.nih.gov/39917132/
- Bikash C. Topical Alternatives for Hair Loss: Beyond the Conventional. Int J Trichology. 2025. Review of 24 articles and technical files; no conflicts declared. https://pubmed.ncbi.nlm.nih.gov/40654553/
- Arruda S, et al. Single-Center, Open-Label Study Study to Evaluate Improvement of Hair Appearance With Novel Hair Growth Serum. J Drugs Dermatol. 2025. Open-label, n=20, 6 months; funding not reported in abstract. https://pubmed.ncbi.nlm.nih.gov/40196948/
- Weir D, et al. Human Platelet Extract (Plated) Hair Serum for Hair Health Improvement: A Double-blind, Placebo-controlled Clinical Study. Plast Reconstr Surg Glob Open. 2025. Double-blind placebo-controlled, n=39; funded in part by Rion Aesthetics. https://pubmed.ncbi.nlm.nih.gov/40104384/
- Bhardwaj V, et al. Artificial Intelligence-Based Personalization of Treatment Regimen for Hair Loss: A 6-Month Clinical Trial. J Drugs Dermatol. 2025. Uncontrolled, 38 enrolled, 27 completed, 24 weeks. https://pubmed.ncbi.nlm.nih.gov/40043278/
- Mann K, et al. A Nonrandomized Clinical Trial Investigating Keratinocyte Growth Factor-Hair Serum for the Prevention of Chemotherapy-Induced Alopecia. J Cosmet Dermatol. 2026. Single-arm Simon two-stage, 20 evaluable; no conflicts declared. https://pubmed.ncbi.nlm.nih.gov/41834767/
- Pyo HK, et al. The effect of tripeptide-copper complex on human hair growth in vitro. Arch Pharm Res. 2007. Ex vivo and in vitro. https://pubmed.ncbi.nlm.nih.gov/17703734/
- Najafi N, et al. A Systematic Review of the Mechanisms and Therapeutic Applications of GHK-Cu (Glycyl-L-Histidyl-L-Lysine-Copper Complex) in Topical Microneedle Delivery: A Case for Expanded Clinical Trials. Arch Intern Med Res. 2026. Systematic review, 64 records retained. https://pubmed.ncbi.nlm.nih.gov/42787770/
Disclosure: This article is for general information only. It is not medical advice. Peptide Skincare has no affiliate links in this article and received no payment from any manufacturer mentioned. Brand names are trademarks of their owners. Peptide Skincare has no relationship with The Ordinary. See a dermatologist to diagnose hair loss.