OBAGI - NU-CIL® Eyebrow Boosting Serum

OBAGI NU-CIL® Medical-Grade Eyebrow Enhancing Serum OBAGI NU-CIL® Eyebrow Enhancing Serum is a clinically developed, medical-grade brow serum formulated to visibly restore fullness, density, and definition to sparse, over-plucked, or thinning eyebrows. Powered by the same advanced peptide complex trusted in the NU-CIL® Eyelash Serum, this formula works at the follicular level to extend the natural brow hair growth cycle — delivering measurably thicker, fuller, and more defined brows without hormonal actives or prescription requirements. Developed by OBAGI Medical — trusted by dermatologists and aesthetic clinicians worldwide for over 35 years — NU-CIL® Eyebrow Serum is the professional-grade solution for brow restoration and enhancement. What OBAGI NU-CIL® Eyebrow Serum Delivers Visibly fuller, thicker brows — targets the anagen (active growth) phase to increase brow hair density Improved brow definition — fills sparse patches and gaps for a more structured, groomed appearance Restoration of over-plucked brows — supports regrowth in follicles that have been repeatedly stressed by waxing, threading, or tweezing Stronger, less brittle brow hairs — conditions the hair shaft to reduce breakage and improve texture Suitable for all brow types — including naturally sparse, age-related thinning, and post-treatment recovery Visible results from 4–6 weeks — with optimal results typically seen at 12–16 weeks of consistent use How OBAGI NU-CIL® Eyebrow Serum Works: The Science Like eyelashes, eyebrow hairs follow a cyclical growth pattern: the anagen phase (active growth), the catagen phase (transition), and the telogen phase (resting and shedding). Years of over-plucking, waxing, or threading — combined with hormonal changes and ageing — can shorten the anagen phase and reduce follicular activity, resulting in permanently sparse or thin brows. NU-CIL® Eyebrow Serum is formulated to reactivate dormant follicles, extend the anagen phase, and nourish the follicular environment — creating the optimal conditions for visible brow regrowth. The formula combines: Myristoyl Pentapeptide-17 — a biomimetic signal peptide that upregulates keratin gene expression within the hair follicle, directly stimulating brow hair fibre production and elongation Myristoyl Hexapeptide-16 — works synergistically to enhance follicular stem cell activity and improve hair anchoring, reducing premature shedding Biotin (Vitamin B7) — an essential co-factor in keratin synthesis; deficiency is directly linked to hair thinning, brittleness, and loss across the brows and scalp Panthenol (Pro-Vitamin B5) — deeply conditions the brow hair shaft, improving flexibility, reducing breakage, and enhancing natural sheen Swertia Japonica Extract — a clinically studied botanical active shown to stimulate follicular stem cells and support the transition from telogen back into the active anagen growth phase Hyaluronic Acid — maintains optimal hydration at the follicular microenvironment, supporting healthy hair emergence and reducing stress-related hair loss This multi-pathway approach — combining peptide signalling, follicular nourishment, and botanical activation — makes NU-CIL® Eyebrow Serum significantly more comprehensive than single-ingredient brow serums or castor oil-based alternatives. Can Over-Plucked Brows Grow Back? What the Science Says One of the most common questions in brow restoration is whether follicles damaged by years of over-plucking can recover. The answer depends on follicular viability: Temporarily dormant follicles — follicles that have been stressed but not permanently scarred can often be reactivated with consistent follicular stimulation and nourishment. NU-CIL® targets precisely this mechanism. Permanently scarred follicles — repeated trauma over many years can cause fibrotic scarring that prevents regrowth. In these cases, results may be partial rather than complete. For best outcomes, begin treatment as early as possible. The longer follicles remain dormant, the lower the likelihood of full reactivation. NU-CIL® is most effective when used consistently over a minimum 12–16 week course. How to Use OBAGI NU-CIL® Eyebrow Serum Ensure the brow area is clean and free of makeup, oils, and other topical products Using the precision applicator, apply a thin layer of serum along and within the brow line — covering sparse areas and the full brow from inner to outer corner Allow to absorb fully before applying brow makeup or other products Apply once daily, preferably in the evening as part of your skincare routine Do not apply to irritated, broken, or inflamed skin Continue use consistently for a minimum of 12–16 weeks for optimal results; maintenance use is recommended to sustain regrowth Pro tip: Apply after your evening cleanser and before heavier moisturisers or facial oils — this ensures maximum absorption into the follicular environment without the serum being diluted or occluded. Who Is OBAGI NU-CIL® Eyebrow Serum Suitable For? NU-CIL® Eyebrow Serum is suitable for adults who: Have naturally sparse, thin, or asymmetric brows and want visible enhancement without microblading or tattooing Have experienced brow thinning due to age, hormonal changes (including thyroid dysfunction or menopause), or nutritional deficiency Are recovering from over-plucking, waxing, or threading and want to support regrowth Are seeking a non-invasive alternative or complement to microblading, brow lamination, or tinting Have experienced brow hair loss following chemotherapy or medical treatment (consult your oncologist before use) Want to maintain and enhance results following a professional brow treatment Not recommended for: use during pregnancy or breastfeeding without medical advice; individuals with active skin infections or inflammation in the brow area; those under 18 years of age. Product Details Brand OBAGI Medical Product NU-CIL® Eyebrow Enhancing Serum Size 5 ml Formula type Peptide & botanical brow serum Application Precision applicator Frequency Once daily (evening recommended) Visible results 4–6 weeks; optimal at 12–16 weeks Dermatologist developed Yes Prescription required No Suitable for All brow types including sparse, thinning, and over-plucked Frequently Asked Questions How long does OBAGI NU-CIL® Eyebrow Serum take to work? Most users notice initial improvements in brow density and fullness within 4–6 weeks of consistent daily use. Optimal results are typically achieved at 12–16 weeks. Brow hair grows more slowly than eyelashes, so patience and consistency are essential — do not discontinue use before the 12-week mark. Will OBAGI NU-CIL® grow back over-plucked eyebrows? NU-CIL® can help reactivate dormant or stressed follicles that have been affected by over-plucking, waxing, or threading. Results depend on follicular viability — follicles that are dormant but not permanently scarred respond best. Begin treatment as early as possible for the highest chance of meaningful regrowth. Can I use NU-CIL® Eyebrow Serum alongside microblading or brow lamination? Yes — NU-CIL® Eyebrow Serum is an excellent complement to microblading and brow lamination. Use it to improve natural brow density before a treatment (for better results) or after (to maintain and enhance regrowth between appointments). Avoid applying directly to freshly microbladed skin until fully healed — typically 4–6 weeks post-procedure. What happens if I stop using NU-CIL® Eyebrow Serum? Brows will gradually return towards their pre-treatment state as the natural growth cycle reasserts itself — typically over 6–10 weeks after discontinuation. To maintain results, continued use is recommended. Many users transition to every-other-day application as a maintenance dose once optimal results are achieved. Is OBAGI NU-CIL® Eyebrow Serum safe for sensitive skin? NU-CIL® Eyebrow Serum is dermatologist-developed and formulated to be well-tolerated. If you have a history of contact dermatitis or sensitivity to cosmetic actives, perform a patch test on the inner arm for 48 hours before applying to the brow area. Discontinue use if irritation, redness, or itching occurs. Can I use NU-CIL® Eyebrow Serum if my brow thinning is hormonal? Hormonal brow thinning — commonly associated with thyroid dysfunction, menopause, or postpartum changes — responds well to follicular nourishment and peptide stimulation. NU-CIL® can support regrowth in these cases, though addressing the underlying hormonal cause with your GP or endocrinologist will produce the best long-term outcomes. NU-CIL® works well as part of a broader treatment approach. Why Buy OBAGI NU-CIL® From a Clinician-Backed Retailer? OBAGI products are professional-grade formulations designed for use under clinical guidance. Purchasing from an authorised, clinician-backed retailer ensures you receive: Authentic, UK-sourced product — not grey-market or counterfeit stock Expert guidance on integrating NU-CIL® into your wider skincare or brow treatment protocol Correct storage and handling — maintaining product integrity and efficacy Access to professional advice if you experience any unexpected reactions or want to combine NU-CIL® with other treatments Counterfeit and grey-market OBAGI products are a known issue in the UK market. Always verify you are purchasing from an authorised OBAGI stockist.