What is eyelash growth serum?
Eyelash growth serum is essentially a treatment for your natural lashes, designed to help them look longer, fuller and healthier over time. Most come in small tubes with a fine brush or wand and, depending on the formula, can help condition the lash hairs, keep them hydrated and reduce breakage – particularly handy if your lashes are feeling a little worse for wear after years of mascara, curling or lash treatments.
As for what’s actually inside? You’ll often spot ingredients like peptides, panthenol, hyaluronic acid and amino acids, which help nourish and condition the lashes so they stay stronger and are less likely to snap. Some formulas also contain prostaglandin analogues, which can have a more noticeable effect on lash length and thickness. So while they may all look pretty similar sitting on the beauty shelf, what a lash serum can actually do for your lashes really comes down to its formula.
Our top lash serum picks:
How should I apply lash serum?
Lash serum should always go onto clean, dry lashes, so I tend to apply mine in the evening once my makeup is off. I’ll usually go over my eyes with a little toner or eye makeup remover too, just to make sure there’s no mascara or skincare lingering around my lash line. “Most lash serums should be applied once a day to clean, dry skin, along the upper lash line, almost as you would apply liquid eyeliner,” explains Caroline Hall, aesthetic nurse and founder of R&R Aesthetics.
And make sure your lashes really are dry before you go in – applying serum to damp skin can dilute the formula and make it more likely to run into your eyes. I’ll normally pat mine dry with a cotton wool pad, and give them a minute before applying. One last thing: wipe any excess serum from the applicator on the inside of the tube first. You only need a small amount, so one light swipe is plenty.
How to choose the right lash serum:
Having tested my fair share of lash serums, one thing I’ve realised is just how different the formulas can be. Some are all about conditioning and strengthening the lashes you already have, while others are designed to have a more noticeable effect on length and thickness. So, before picking one purely on the promise of longer lashes (guilty), it’s worth having a quick look at what’s actually inside.
- Conditioning lash serums: Think of these as skincare for your lashes. They’re packed with conditioning ingredients to keep lashes hydrated, healthy and less likely to break – which can help them look fuller and stronger in the process.
- Peptide-based lash serums: Probably the type I come across most often, these use peptides alongside conditioning ingredients to support stronger, healthier-looking lashes over time. The Ordinary Multi-Peptide Lash and Brow Serum and UKLASH Complex Peptide Lash Serum are two examples.
- Prostaglandin analogue lash serums: These are the formulas that can deliver more noticeable changes in lash length and thickness, but they’re also the ones worth doing your homework on. “These ingredients can produce impressive growth, but they’re not necessarily the right choice for everyone,” says Caroline Hall. They can come with potential side effects, including irritation and darkening of the eyelid skin, so this is one ingredient I’d always check for before buying.
How long does lash serum take to work?
Realistically, we’re talking months rather than days. “Lashes grow in cycles, so you need to give a serum time to work,” says Hall. “You may start noticing a difference after around six to eight weeks, with more noticeable results after three to four months.”
I’ve found taking a photo before I start a new serum genuinely helpful, too. When you’re looking at your lashes every day, tiny changes are incredibly difficult to spot, whereas comparing pictures a couple of months apart gives you a much better idea of whether anything has changed. And don’t be tempted to speed things along with extra product: as Hall puts it, “Consistency is much more important than applying lots of product.”
Should I apply lash serum in the morning or at night?
There’s no hard and fast rule here, and honestly, the best time to apply your lash serum is whenever you’re actually going to remember to use it. Most of the formulas I’ve tried have slotted into my evening routine – it makes sense when my makeup is off, I’ve cleansed and I’m already working my way through my skincare.
The important thing is that your lash line is completely clean and dry before you go in. And, because every formula is slightly different, check the instructions on yours first – some recommend once-a-day application, while others can be used morning and evening. Personally, I keep mine next to my skincare rather than tucked away with my makeup; otherwise, there’s a very good chance I’ll forget it exists.
Are lash serums safe?
Your lash line is a pretty delicate place to be experimenting with products, so I wouldn’t ignore irritation in the hope that your eyes will eventually get used to a formula.
“I’d avoid anything that repeatedly causes redness, itching, burning or irritation around the eyes,” says Hall. If that keeps happening, stop using it rather than trying to persevere.
It’s particularly important to know whether your serum contains a prostaglandin analogue. Hall explains that these ingredients have been associated with side effects including irritation and darkening of the eyelid skin, as well as changes around the eye area with some prostaglandin-related products.
If you have sensitive eyes or an existing eye condition, Hall recommends speaking to an appropriate healthcare professional before using one. And whichever formula you’re using, your eyes shouldn’t have to suffer for the sake of longer lashes.
Can I use lash serum with lash extensions?
Yes, you can generally keep using a lash serum when you have extensions – but this is one occasion where I’d be particularly picky about the formula.
“With extensions, I’d choose an oil-free formula as oils can interfere with the adhesive,” says Hall. So, before putting your usual serum anywhere near a fresh set, check the ingredients and the product instructions, as well as any aftercare advice from your lash technician.
After all, if I’ve just spent the time and money having a fresh set of extensions applied, I definitely don’t want my skincare routine helping them fall out any sooner than they need to.