Obagi Nu-Cil for Lashes & Brows: A UK Clinician's Guide
Most lash and brow serums that actually work contain prostaglandin analogues — the same class of drug used to treat glaucoma, which turned out to lengthen eyelashes as a side effect. They work, but they come with trade-offs: periorbital darkening, occasional iris colour change, and in some patients, fat loss around the eye.
Obagi's Nu-Cil range is the clinical answer to that trade-off. It delivers visibly fuller lashes and brows without prostaglandins, using a different mechanism entirely. This guide explains what's in the two Nu-Cil facial serums, how they work, and when to expect results.
The prostaglandin problem — and why Nu-Cil avoids it
Prostaglandin-based lash serums (bimatoprost, isopropyl cloprostenate and related compounds) work by extending the anagen — or growth — phase of the lash cycle. That's effective, but prostaglandins act on multiple tissues. Long-term use is associated with:
- Hyperpigmentation of the skin around the eye
- Iris darkening, particularly in lighter eye colours
- Fat atrophy in the periorbital area
- Worsening of dry-eye symptoms
Nu-Cil takes a different approach. Both the lash and brow serums use peptide-based complexes to stimulate the follicle directly — without acting on prostaglandin receptors. That means none of the side effects, while still producing measurable results.
Obagi Nu-Cil Eyelash Enhancing Serum
The Nu-Cil Eyelash Enhancing Serum uses Obagi's proprietary Biomimetic Lash Complex. It extends the natural growth phase of the lash cycle and reduces shedding — so over time, more lashes are present on the lash line at any given moment, each one longer and thicker.
Clinical results:
- Visibly fuller lashes typically appear from around week 6
- Most patients see full results by 90 days of daily use
- Continued use maintains density — lashes will gradually revert if use stops
How to use: Apply a single stroke along the upper lash line once daily, evening only, to clean dry skin. One tube typically lasts 12 weeks.
Who it suits: Anyone wanting denser, longer lashes without the risks of prostaglandins — particularly patients with light-coloured eyes, a history of periorbital pigmentation, or sensitivity to eye drops.
Obagi Nu-Cil Eyebrow Boosting Serum
Brow thinning is more common than people admit. Years of tweezing, threading and waxing, combined with hormonal changes and the natural thinning that comes with age, leave many adults with sparse, patchy brows by their 40s and 50s.
The Nu-Cil Eyebrow Boosting Serum uses Obagi's NouriPlex Technology — a blend of biotin, peptides, and amino acids delivered directly to the brow follicle. Like the lash version, it's prostaglandin-free and safe for daily use around sensitive eyes.
Clinical results:
- Visibly fuller brows from around week 8
- Improved texture and conditioning of existing brow hair throughout
- Suited to over-tweezed, patchy or age-related brow thinning
How to use: Apply once or twice daily along the length of the brow to clean dry skin. Allow to absorb fully before applying other skincare or makeup.
Using both together
The lash and brow serums are designed to be used in combination. There's no interaction between them — they target different follicles — and many patients use both as part of an overall periorbital anti-ageing routine alongside an eye cream.
A typical order of application:
- Evening cleanse
- Nu-Cil Eyelash Serum along the upper lash line
- Nu-Cil Eyebrow Serum along both brows
- Eye cream of choice — for example, Obagi Elastiderm Eye Complete Complex
- Face retinoid or treatment serum
- Moisturiser
Realistic expectations
Nu-Cil is not a dramatic 4-week transformation. It is a slower, safer, more sustainable approach than prostaglandin serums — with the real advantage being that results are maintainable long-term without the side-effect profile that makes prostaglandin serums unsuitable for ongoing use in many patients.
Expect visible change from 6–12 weeks of consistent daily application. Expect results to maintain only with ongoing use.
Accessing Nu-Cil in the UK
Nu-Cil is available without prescription. Both the lash and brow serums ship same-day or next-day from our warehouse. As an authorised Obagi Medical UK stockist, every product is sourced directly from the official UK distributor.
If you'd like advice on whether Nu-Cil is appropriate for you — particularly if you've previously used prostaglandin serums and want to transition — a free written skin assessment is available with our clinician.
start a free written skin assessment →
This guide is for general information. Individual responses to topical skincare vary. If you have an existing eye condition or use prescribed eye drops, consult your clinician before starting any new lash or brow serum.