For me, the words, “You really don’t know what you got until it’s gone,” rings true when I think about my eyelashes. You see, I used to have full, thick, and long lashes for a short moment in time. They were so good that I would get stopped mid-conversation sometimes and asked how I got my eyelashes looking so good.

My secret? Well, ironically (and unfortunately) it was my eye drop medication for my glaucoma. The drops I was on for a few years were made with the same ingredients as Latisse, hence the amazing growth. Eventually, my ophthalmologist took me off them in favor of other drops so my lashes turned back into a “pumpkin,” aka I was stuck with the sparse, thin, and short ones I was born with.

So needless to say, I’m always looking for products that can give my lashes a boost. I’m talking volume-pumping mascaras, falsies, and lately, I’ve been considering a serum. It’s taken me a while to find one to actually buy—not because there aren’t enough to choose from (there are so many), but because I don’t really want to spend a ton of money on something that won’t quite work for me. And most importantly, I want to make sure I’m using the serums safely. So, I decided to ask some experts for their best application tips and for some of their recs. Read along to see what I learned.

If you’re not quite familiar with eyelash serums, they’re designed to make lashes longer and thicker. “Most are clinically developed to address the visible signs of thinning and/or inadequate eyelashes and, with committed daily use, can visibly improve the overall health of the lashes,” explains Joie Tavernise, medical esthetician and founder of Manhattan clinic, JTAV Clinical Skincare. “Various eyelash serums have been on the market for years, but I have seen their popularity grow in recent years. People want to embrace their natural beauty and one easy way to do this is with longer, thicker lashes.”

And while a lot of people seem to be using these serums, I wondered if they were safe and if there were any side effects. It turns out they’re relatively okay to use. “Lash serums are generally safe for use however some sensitive eye consumers may experience redness or irritation depending on sensitivity to certain ingredients and depending on the lash serum,” says Celebrity Esthetician Joshua Ross of SkinLab.

When shopping for an eyelash serum, there are some effective ingredients to look for. “The ingredients most proven to help lashes grow are prostaglandin analogs like bimatoprost and other similar molecules,” says SkinSpirit Medical Director and co-founder Dean Vistnes, MD, FACS.

Other ingredients include peptides, amino acids, vitamins (like vitamin B5), biotin, and conditioners or hydrators (like hyaluronic acid). “These ingredients are helpful because they nourish and hydrate, strengthening lashes and stimulating growth,” Tavernise says.

First, you should make sure your lash and eye areas are clean. Next, apply a thin layer directly to your lash line. Tavernise recommends starting at the inner corner and moving out towards the outer lash line (towards your temple). Give it enough time to dry (about five to 10 minutes) before applying mascara. And make sure you’re following the manufacturer’s directions on how often you should be using the product.

Ross also advises that you should frequently clean the applicator with soap and water to prevent bacteria.

It’s all about consistency if you want the serums to actually work. “With any effective product, it takes time to see true results,” Tavernise says. “I suggest applying eyelash serum twice a day consistently, and you will most likely see growth and increased lash density after three months.”

Vistnes says the two best-known products that have effective active ingredients are Latisse and Revitalash. Latisse is one you’ll have to get prescribed, but again, it can make your lashes look so much longer. Senior beauty editor Erin Jahns tried it and saw results in about six weeks.

Vistnes adds that Revitalash works similarly to Latisse, but has another component of creating a curl in the growth pattern of the lashes

“I consistently see sustained and noticeable results on clients using GrandeLash MD,” Ross says. “It contains just the right amount of active ingredient to see visible results that are sustainable. In addition, this specific brand has a low occurrence of irritation. Some of the hero ingredients include amino acids, hyaluronic acid, and vitamin E which are known to improve the keratin in the hair follicle of the lash while not being irritating.”

“My specially-developed JTAV Clinical Skincare Eyelash Enhancing Serum is my favorite eyelash serum,” Tavernise says. “I developed it because I wanted a product that I could trust would deliver real results. What’s even better is that it has not been associated with darkening of the eyes, color changes, or periorbital hollowing, which are some issues that have been noted as side effects of lash serums. JTAV Clinical Skincare Eyelash Enhancing Serum is formulated with powerhouse photo-peptides and vitamins to support the structure of the follicle. It is also compatible with eye makeup and eyelash extensions so you don’t have to worry about it interfering with your lash routine.”

NeuLash’s serum is formulated with sodium hyaluronate for hydration, softness, elasticity, and shine. There are also amino acids, peptides, biotin, panthenol, and pumpkin seed extracts to to promote strength and nourish the lashes.

Dr. Lara Devgan’s lash serum is a popular favorite that extends the eyelash life cycle and supports growth. It contains vitamin B5, phyto peptides, and clover flower extract.

Lashes can get damaged through makeup, eyelash curlers, extensions, and falsies. Give them some TLC with this conditioning serum.

This affordable formula is gentle and non-irritating. You can use it on both your brows and lashes to encourage growth and strengthen them.

With a plant-based formula, Vegamour’s serum contains phyto actives to get your lashes longer and thicker. Ingredients include red clover and mung bean to prevent hair loss, and an amino acid peptide to regenerate the hair follicles.

This eyelash-enhancing serum contains NouriPlex Technology, which is a blend of four key ingredients to improve thickness, volume, and density. Other ingredients include biotin, dehydrolantanoprost, sodium hyaluronate, and panthenol.

Dior’s primer serum will enhance the volume, curl, and wear of mascara. It has a balm texture that’s enriched with cornflower floral extract, which will make your mascara look even more intense.

LashFood’s formula is 99.49% natural and completely nourishes and conditions your lashes, especially if they’re damaged. It contains a blend of ingredients that jumpstart the hair follicles and promote new growth.

Maya Chia’s treatment is both for the lashes and brows. It encourages longer, fuller, and healthier lashes and brows, while also accentuating them temporarily.

You might see results with this serum in just six weeks. It contains a peptide complex to enhance the length, strength, and thickness of the lashes; chamomile flower extract to soothe and balance; and ginseng root extract to strengthen and encourage new growth.

You can even use this serum on lash extensions. It’s formulated with a Hexatein 1 Complex (to condition and fortify), polypeptides, biotin, panthenol, amino acids, soybean oil, and pumpkin seed extract.

Pacifica’s serum is a vegan formula that protects and conditions the lashes. It acts as a primer so it will just make your mascara look even better.

You might see some improvement in your lashes in just four weeks with this serum—although the normal time frame is 12 weeks. They’ll look more voluminous, strengthened, and conditioned.

Pronexa’s botanical serum not only makes your lashes longer, fuller, and thicker, but it also adds sheen to them. You can also use them on your brows.

We’re already big fans of The Ordinary, so we’re excited about this lash and brow serum. The lightweight formula is enriched with four peptide technologies to make your lashes look thicker and healthier.

You don’t have to worry about irritation here—people who wear contact lenses and have sensitive eyes can use this gentle serum. It contains nine botanical actives to nourish both your lashes and brows.

A two-in-one, this is both a mascara and a serum. It’s formulated with hyaluronic acid, plant proteins, nutrients, and collagen to repair and nourish the lashes. And the mascara part of it is lengthening and provides intense color.

The biotin and panthenol in this formula give a lush look to your lashes, while conditioning ingredients and pumpkin seed extract will make thin, sparse lashes look better.

One of the big ingredients in this formula is arginine, which can restore hair (aka your lashes and brows). It comes with a flocked tip applicator so you can easily apply to some hard-to-reach spots.

Wet N Wild’s product is a serum-gel formula that plumps up your lashes and brows, making them look way thicker. Ingredients include biotin, peptides, niacinamide, castor oil, and vitamin E to nourish and hyrdate.

Milani’s serum is vegan and cruelty-free. It works to improve the appearance of both your lashes and brows, helping them look fuller and healthier.

Next, Decoded: How to Choose the Correct Mascara Wand to Get the Lashes of Your Dreams