Hair-growth complexes: what the evidence shows for hair fall and fullness
Redensyl, Capixyl, Procapil and similar branded complexes are popular in hair serums. Human evidence is thin and mostly uncontrolled. CSL formulation scientists explain what can and cannot be claimed.
By CSL Formulation team · Evidence checked by CSL scientists
At a glance
- What it is
- Branded blends of plant extracts, flavonoids and peptides, such as Redensyl, Capixyl, Procapil, Anagain and Baicapil, sold for hair fall and density
- Main benefits
- Less hair fall and fuller-looking, thicker-feeling hair in small studies; no proven benefit over minoxidil
- Levels tested in trials
- 1% Capixyl and 1% Procapil; 3% of each of five complexes; 5% Procapil alongside minoxidil; many studies do not state levels
- Time to results
- 12 weeks to 12 months in published studies
- Watch for
- Supplier-funded, open-label studies; combination products that make it impossible to credit one complex; medicine-style claims
01What is it?
Hair-growth complexes are ready-made ingredient blends from cosmetic suppliers. Redensyl combines a dihydroquercetin glucoside, an EGCG derivative, glycine and zinc. Capixyl pairs acetyl tetrapeptide-3 with red clover extract, and Procapil pairs biotinoyl tripeptide-1 with apigenin and oleanolic acid. Anagain (pea sprout extract), Baicapil and topical saw palmetto are used in the same way.
02What it does
Suppliers report that these blends act on the hair follicle in laboratory tests, for example by supporting the growth phase, calming inflammation or reducing the effect of androgens. In people, the few published studies report less hair fall and small gains in hair count, density or thickness over three to twelve months. Most of these studies had no placebo group, so part of the effect may come from the vehicle, massage or expectation.
03The evidence
Studies below were checked against the publisher, DOI or journal record on 26 Sep 2026. We list design and size so you can judge the strength of each result.
| Study | Design | Who and how long | What it found |
|---|---|---|---|
| Patel et al. 2025, IP Indian Journal of Clinical and Experimental Dermatology Source | Open-label, multicentre real-world study, two groups, funded by Zydus Healthcare | 400 adults with pattern hair loss, 4 months, 5% minoxidil with Procapil, Redensyl, caffeine and Transcutol vs plain 5% minoxidil | Hair thickness rose 4.8 µm with the combination vs 2.7 µm (not significant) with plain minoxidil; terminal hair density rose 27.5 vs 24 hairs/cm². Both groups had minoxidil, and the study was not blinded. |
| Chandrashekar et al. 2025, Journal of Cutaneous and Aesthetic Surgery Source | Open-label, three-arm comparative study, no placebo | 45 women with excess shedding (telogen effluvium), 90 days, three peptide serums including a Redensyl and aminexil serum | Hair fall fell 26.3% with the Redensyl serum, 23.9% and 54.6% with the other two serums; no side effects. Small groups (14 each) and no untreated comparison. |
| Bansal and Bansal 2024, Journal of General-Procedural Dermatology and Venereology Indonesia Source | Open-label, single-arm study, no control group | 110 adults with pattern hair loss (70 completed), 16 weeks, serum with 3% each of Capixyl, Redensyl, Procapil, Anagain and Baicapil | Hair density rose about 10% (76.8 to 84.5) and hair thickness about 8% (38.7 to 41.7 µm); no side effects. The authors note it was neither randomised nor controlled, and over a third dropped out. |
| Fahim et al. 2024, Journal of Pakistan Association of Dermatologists Source | Randomised controlled trial, add-on design | 140 people with pattern hair loss, 12 months, 5% minoxidil twice daily vs 5% Procapil alternated with minoxidil | Adding Procapil gave a greater rise in hair count than minoxidil alone (p = 0.0001), with better satisfaction and dermatologist scores. It tests Procapil with a medicine, not on its own. |
| Eslahi et al. 2022, Our Dermatology Online Source | Comparative two-group trial with coded products | 40 men with pattern hair loss, 24 weeks, tonic with 1% Capixyl, 1% Procapil and 0.5% rosemary extract vs 2% minoxidil | Photographs showed improvement in 57% with the tonic vs 8% with 2% minoxidil; staff rated 60% vs 30% improved. Very small, and 2% minoxidil is a weak comparator for men. |
Hair-growth complexes have a plausible laboratory story but weak human evidence: small studies, mostly without a placebo, usually testing several actives at once and often funded by the maker. None shows a complex outperforming 5% minoxidil on its own. Claims should stay cosmetic, for example “reduces hair fall due to breakage”, “fuller-looking, thicker-feeling hair”, and be backed by the brand’s own product test.
04How CSL formulation scientists use it
- Use the supplier’s recommended level (commonly 1–5% of the ready-made complex) and check whether that figure refers to the complex or the pure active, since trials report it differently.
- Most complexes are water- or glycol-soluble and suit leave-on scalp serums, tonics and sprays; rinse-off shampoos give little contact time and weak support for growth-related claims.
- Check pH, preservative and ethanol compatibility with each supplier’s data, and run stability and scalp compatibility tests on the finished formula.
- To support claims, run a product-specific study with a vehicle-controlled design and objective measures such as hair-pull tests, phototrichograms or hair counts, rather than relying on supplier data alone.
05Regulatory and claims
These complexes are sold as cosmetic ingredients. Minoxidil is a medicine in most markets, so a product cannot contain it as a cosmetic, and cosmetic claims must not say “regrows hair”, “treats alopecia” or “blocks DHT”. In the EU, claims must be truthful and supported by evidence under the common claims criteria. CSL regulatory specialists confirm the status of each complex and its components in each target market and check that supplier claims are not copied straight onto packs.
06Questions brands ask
Is Redensyl as good as minoxidil?
There is no good evidence for that. The published comparisons are small, mostly unblinded, often use weak 2% minoxidil or add the complex on top of minoxidil, and some are funded by the product maker.
Can a product claim to regrow hair?
No. Hair regrowth and treating hair loss are medical claims. Cosmetic products can claim less hair fall due to breakage or fuller-looking hair if the finished product has been tested for it.
Is it worth combining several complexes?
Many products do, and combination studies report modest gains, but none shows which ingredient does the work. A tested single complex at a clear level is easier to substantiate.
07References
- Patel K, Yadalla HKK, Srinivasa S, Rekha Singh TN, Varsha DV; PRO-ACT study group. A prospective multicentric real-world evidence study to evaluate the safety and effectiveness of topical minoxidil (5%) in combination with Procapil, Redensyl, caffeine and Transcutol vs plain minoxidil (5%) topical solution in patients with androgenetic alopecia: PRO-ACT. IP Indian J Clin Exp Dermatol. 2025;11(3):394–399. Link
- Chandrashekar BS, Roopa MS, Kusuma MR, Madura C, Shenoy C, Lakshmi Narayna N, Ghoshal P. Comparative analysis of various hair peptide serums in managing telogen effluvium in females: efficacy, safety, and patient satisfaction. J Cutan Aesthet Surg. 2025. Link
- Bansal G, Bansal R. A prospective study in the treatment of androgenic alopecia using combination of procapil, capixyl, redensyl. J Gen-Proced Dermatol Venereol Indones. 2024;8(2):70–77. Link
- Fahim S, Khoso, Khan, Bakhtiar. Combining topical minoxidil with procapil; an assessment of their comparative efficacy in androgenetic alopecia: a randomized control trial. J Pak Assoc Dermatol. 2024;34(2):384–391. Link
- Eslahi E, Hashemi N, Shamaei S. Effectiveness of the active ingredients (Capixyl, Procapil, and rosemary extract) of the Trust tonic for the treatment of androgenetic alopecia in comparison to minoxidil. Our Dermatol Online. 2022;13(4):346–351. Link
Used in:
Update log
- Evidence reviewed and page published by CSL scientists
This page summarises published research for brands and formulators. It is general information, not medical advice, and results in studies depend on the full formula tested.
