Inside the Restore Hair Serum: The Science of Your Day-5 Scalp Routine

The Restore Hair Serum is the 30 ml leave-in companion to the Restore Micro-Infusion Hair Density kit. It carries the same scalp actives as the sterile ampoules in your kit, in a leave-on formula made for the days between and after treatment. This guide explains what is in the bottle, the published research behind each active, and exactly when and how to use it. Every numbered reference links to a peer-reviewed journal article.

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What the Restore Hair Serum is for

A micro-infusion course works on a weekly rhythm: one stamped treatment a week, then six nights of recovery. The Restore Hair Serum is your in-between & after-treatment step. Applied from day 5 after each treatment, once the scalp has settled and the micro-channels have long closed, it keeps the same actives working at the follicle line on the nights the stamp stays in the drawer.

It matters that the two products are different by design. The kit ampoules are sterile and preservative-free because they are infused through open micro-channels. The 30 ml serum is a leave-on for intact skin, so it uses a standard cosmetic preservative system to stay safe in a multi-use bottle. That is exactly why the serum is never applied to freshly stamped skin: preserved products belong on an intact scalp, and yours will be by day 5.

What is in the bottle

The serum is light, non-greasy and fragrance-free, made for the scalp rather than the hair fibre. No essential oils, no minoxidil, and it is vegan. These are the actives and the published research behind them:

• Redensyl, Capixyl and Procapil. This trio of botanical and peptide scalp actives is one of the most popular cosmetic combinations for the look of hair density, and it has begun to accumulate published clinical data of its own. A 2024 prospective study followed adults with thinning hair using a topical serum built on this combination for 16 weeks and reported significant improvements in measured hair density and hair shaft diameter, with no adverse effects observed [1]. It was an open-label study without a control group, so it sits below the big randomised trials in strength, but the direction is encouraging and consistent with the ingredient-level research below.
• Procapil (biotinoyl tripeptide-1) with caffeine. A 2023 clinical assessment tested a topical formulation of Procapil at 3% together with caffeine, the same pairing used in Restore, and reported improvement in the appearance of thinning with good tolerability [2].
• Caffeine. One of the best-studied cosmetic scalp actives. A 2025 review details its mechanisms in the follicle, from phosphodiesterase inhibition to support for the active growth phase of the hair cycle [3].
• Copper tripeptide-1 (GHK-Cu). A regenerative peptide with a long research history in skin repair. A 2025 review of tripeptides describes how GHK-Cu supports the skin's own renewal processes at remarkably low concentrations [4]. Your scalp is skin, and follicle health is inseparable from the condition of the skin it lives in.
• Niacinamide. Included for scalp-barrier support and soothing, with an extensive body of clinical evidence in skin care [5].
• Panthenol, beta-glucan and sodium hyaluronate. The conditioning and hydration base that keeps the scalp comfortable and the formula light enough to disappear into the part line.

Why treat the scalp at all?

Every hair grows from a follicle cycling through growth, transition, rest and shedding phases, and hair looks thinner when that balance shifts toward rest [6][7]. The follicle is a living structure embedded in scalp skin, which is why modern hair care treats the scalp as skin care: the environment around the follicle matters. Consistent scalp care, alongside a needling routine whose published evidence keeps growing [8], is how you support the look of fuller, denser hair over a course [9].

How to use it

1. During a micro-infusion course: apply from day 5 after each weekly treatment, at night, onto a clean, dry scalp. Never apply it to freshly stamped skin; the sterile ampoule is the only thing that touches a treatment-night scalp.
2. Apply to the scalp, not the lengths. Part the hair and apply a few drops along the part line and any areas of concern, then massage in gently with fingertips for 30 to 60 seconds.
3. Leave it in. It is a leave-on: no rinsing. Style as normal.
4. Between courses or on its own: use nightly or every second night as a standalone scalp serum.
5. Be consistent and patient. Hair works on a slow clock; studies of scalp actives typically run 12 weeks to 6 months [1][8]. Take before photos and review them monthly.

One rhythm to remember: the micro-infusion stamp comes out once a week, and only once a week. Stamping more often does not speed anything up; the biology sets the pace. The serum is the only product in the routine that is used between treatments.

Good to know

Fragrance-free, no essential oils, no minoxidil, vegan, and formulated to the same exclusion rules as the whole Restore system. If you have a scalp condition, are pregnant or breastfeeding, or are using prescription hair treatments, check with your GP or dermatologist before starting anything new. Persistent or sudden hair loss deserves a proper diagnosis; a cosmetic serum supports the look of your hair, it does not treat a medical condition.

Questions about your hair? Talk to us, free

If you would like help building your routine, want to know whether the Hair Density kit and serum are right for you, or would like to review your progress photos with us during your course, book a free virtual skin consultation. It costs nothing, and it is the same consultation we give our clinic clients.

Book a free virtual skin consultation

Shop the edit

Everything mentioned above is in one place: the Restore Hair Serum 30ml and the Restore Micro-Infusion Hair Density kit. For the full instructions and aftercare for your kit, see the complete Restore Micro-Infusion guide.

References

1. Bansal, G., & Bansal, R. (2024). A prospective study in the treatment of androgenic alopecia using combination of procapil, capixyl, redensyl. Journal of General-Procedural Dermatology and Venereology Indonesia. doi.org/10.7454/jdvi.v8i2.1200
2. Samadi et al. (2023). Assessment of the efficacy and tolerability of a topical formulation containing caffeine and Procapil 3% for improvement of male pattern hair loss. Journal of Cosmetic Dermatology. doi.org/10.1111/jocd.16102
3. Szendzielorz & Spiewak (2025). Caffeine as an Active Molecule in Cosmetic Products for Hair Loss: Its Mechanisms of Action in the Context of Hair Physiology and Pathology. Molecules. doi.org/10.3390/molecules30010167
4. Adnan et al. (2025). Exploring the Role of Tripeptides in Wound Healing and Skin Regeneration: A Comprehensive Review. International Journal of Medical Sciences. doi.org/10.7150/ijms.118118
5. Boo (2021). Mechanistic Basis and Clinical Evidence for the Applications of Nicotinamide (Niacinamide) to Control Skin Aging and Pigmentation. Antioxidants. doi.org/10.3390/antiox10081315
6. Lin et al. (2022). Morphogenesis, Growth Cycle and Molecular Regulation of Hair Follicles. Frontiers in Cell and Developmental Biology. doi.org/10.3389/fcell.2022.899095
7. Natarelli et al. (2023). Integrative and Mechanistic Approach to the Hair Growth Cycle and Hair Loss. Journal of Clinical Medicine. doi.org/10.3390/jcm12030893
8. Pei et al. (2024). Efficacy and safety of combined microneedling therapy for androgenic alopecia: A systematic review and meta-analysis of randomized clinical trials. Journal of Cosmetic Dermatology. doi.org/10.1111/jocd.16186
9. Rosenthal & Conde (2024). Management of androgenic alopecia: a systematic review of the literature. Journal of Cosmetic and Laser Therapy. doi.org/10.1080/14764172.2024.2362126

The Restore Hair Serum is a cosmetic product and is covered by our 90-Day Money-Back Guarantee. This article is general information about published research and cosmetic hair care. It is not medical advice, and cosmetic products do not treat medical conditions. Persistent hair loss can have medical causes that deserve a proper diagnosis; please see your GP or dermatologist.