Eyebrow serum

An eyebrow serum is a leave-on cosmetic that you brush along the brow line, usually once a day before bed. It does not create new hair follicles. It works with the hairs you already have, conditioning them and keeping the skin around them comfortable, so brows look fuller and more defined over time. Brow hairs grow for a few months, then rest and shed, so any visible change follows that slow rhythm. That is why serious brands talk in weeks, not days. If you are treating your lashes too, our serums for eyelashes sit in the same range.

Three types of brow serum, and how they differ

Almost every product on the UK market falls into one of three groups. The difference sits in the ingredient list, not in the marketing.

• Peptide serums. Peptides are short chains of amino acids. They are usually combined with panthenol, biotin or ginseng extract. This is the most common cosmetic route.
• Conditioning oils and blends. Castor oil, squalane, vitamin E. These aim at suppleness, shine and less breakage rather than density.
• Prostaglandin analogue serums. Ingredients such as isopropyl cloprostenate. Pharmacologically active next to the eye, and the reason for the paragraph below.

Where we draw the line on ingredients

In February 2026 the EU Scientific Committee on Consumer Safety concluded that three prostaglandin analogues used in lash and brow serums cannot be considered safe for cosmetic use. Reported effects include permanent darkening of the iris and loss of fat around the eye, which changes the contour of the eye socket. Most packs do not mention this. We therefore keep our brow shelf free of these ingredients and stay with formulas that are suitable for daily use close to the eye.

How we choose the brow serums we stock

We judge a serum on three things: the type of ingredient, the amount stated on the label and whether the combination makes sense so close to the eye. Peptide and panthenol formulas pass. Serums built on a prostaglandin analogue do not, even when they sell well elsewhere. We buy directly from the brands, so every bottle is authentic, and our compliance team reads the full ingredient list before a product goes live. We test products ourselves and independent labs spot-check batches. In more than ten years we have learned that a short, clear ingredient list beats a long one. Read how we select our brands.

Who it suits and what to expect

A brow serum suits you if your brows are thin, patchy after years of plucking, or fragile after lamination or tinting. It works best where the follicle is still active. If an area has been bare for many years, expect better condition and shine rather than full regrowth: useful, but worth knowing before you buy. Give it four to six weeks for the first signs and eight to twelve weeks before you judge it. Skip days and the clock effectively restarts.

Brows also respond to what happens under the skin. Some people pair a serum with supplements for hair growth and keep the area simple otherwise: no oils layered on top, no makeup remover rubbed hard into the brow.

A serum stays a cosmetic step. It is not a treatment for hair loss with a medical cause, so if your brows thin quickly or in clear patches, speak to your GP first. For a wider routine, look at our range for hair, skin and nails.