Most lash serums that visibly lengthen lashes work the same way: they contain a prostaglandin analog, a cousin of the glaucoma drug that made Latisse the only FDA-approved eyelash treatment. Those ingredients are why the popular serums work, and also why they carry side effects that peptide-only serums don’t. Before choosing a brand, decide which kind you want.
The short answer: for the most visible results at a reasonable price, get GrandeLASH-MD (about $36). It’s the best-selling lash serum in the US and uses a low dose of isopropyl cloprostenate. RevitaLash Advanced is the premium option, and Babe Lash Essential Serum is a cheap way to try a prostaglandin serum. If you have sensitive eyes, wear contacts, or would rather avoid prostaglandins altogether, choose GrandeLASH-SENSITIVE. Results will be gentler. For the strongest effect, ask a doctor about Latisse (bimatoprost 0.03%).
Our Picks at a Glance
| Serum | Best for | Active type | Price |
|---|---|---|---|
| GrandeLASH-MD | Best overall | Prostaglandin analog (isopropyl cloprostenate) | About $36 |
| RevitaLash Advanced | Premium | Prostaglandin analog (DDDE) | About $100 for 2 mL |
| Babe Lash Essential Serum | Trying one for less | Prostaglandin analog (isopropyl cloprostenate) | About $29 for 1 mL |
| GrandeLASH-SENSITIVE | Sensitive eyes, no prostaglandins | Peptides, botanicals, vitamins | About $28 for 2 mL |
Prostaglandin Serums vs. Peptide Serums
Prostaglandin analogs lengthen the growth phase of the lash follicle, so lashes grow longer, thicker and darker before they shed. The prescription version, bimatoprost 0.03% (Latisse), was approved by the FDA in 2008. In its main trial, 78% of people using it had a meaningful improvement in lash prominence after 16 weeks, compared with 18% using a placebo (Smith et al., Journal of the American Academy of Dermatology, 2012).
Cosmetic serums use related compounds, mainly isopropyl cloprostenate and dechloro dihydroxy difluoro ethylcloprostenolamide (DDDE). In a 2026 study of 79 lash serums, about 30% contained a prostaglandin analog (Couteau and Coiffard, Annales Pharmaceutiques Françaises, 2026). They aren’t reviewed by the FDA the way Latisse is, and their doses and long-term safety aren’t publicly documented.
Peptide serums use ingredients like biotin, panthenol, peptides and plant extracts to condition lashes and reduce breakage. They’re gentler, but there are no comparable trials showing they make lashes grow, so expect lashes that look healthier and break less rather than dramatically longer.
Side effects of prostaglandin serums
Prostaglandin analogs are drugs that affect tissue around the eye. The known side effects of the prescription versions apply to cosmetic serums too:
- Redness, itching and dry, irritated eyes. In a small 2026 study, six weeks of daily DDDE serum use reduced tear film stability and increased eye redness in healthy women (Sánchez González et al., Eye & Contact Lens, 2026).
- Darkening of the eyelid skin along the lash line. It usually fades after you stop.
- Eye color change. Prostaglandin eye drops can permanently darken light-colored irises. It’s rare with serums applied to the lash line, but France’s health safety agency, ANSES, has warned about it.
- Hollowing around the eyes. Long-term use of prostaglandin eye drops can cause fat loss around the eye, called prostaglandin-associated periorbitopathy, which makes the upper eyelid look sunken.
- Hair growth where the serum lands on the skin.
In early 2026, the European Commission’s Scientific Committee on Consumer Safety concluded that isopropyl cloprostenate, DDDE and a third analog are not safe in eyelash and eyebrow cosmetics at any concentration it was asked to assess. That opinion isn’t a ban yet; an EU restriction would come later. US rules haven’t changed.
Skip prostaglandin serums if you’re pregnant or breastfeeding, have glaucoma or use eye-pressure drops, have had eye surgery or inflammation, or are being treated for any eye condition, unless your eye doctor approves. If you wear contacts, take them out before applying and wait 15 minutes to put them back in.
Best Overall: GrandeLASH-MD
Best overall
GrandeLASH-MD Lash Enhancing Serum
The best-selling US lash serum, with a low dose of isopropyl cloprostenate and results in about 4 to 6 weeks.
GrandeLASH-MD is the lash serum most people end up with, and for good reason. It costs about $36, has more than 60,000 Amazon ratings, and contains a small amount of isopropyl cloprostenate, along with amino acids, hyaluronic acid, vitamins and plant extracts. Grande, which sells it as the top lash and brow serum in US prestige beauty, says a 2 mL tube lasts about three months.
You paint a thin line of serum along the upper lash line once a day with the felt-tip applicator, like liquid eyeliner. Grande says to expect longer-looking lashes in 4 to 6 weeks. Once you’re happy with the length, switch to every other day for maintenance. If you stop, lashes gradually return to their old length as they shed and regrow over a few months.
The side effects above apply, most commonly itchy or red eyes in the first weeks and a faint darkening along the lash line. Apply only a single thin stroke, keep it out of the eye, and don’t apply it to the lower lashes, which pick up product when you blink.
Buy it if you want the most results per dollar from a cosmetic serum and don’t have an eye condition.
Best Premium Pick: RevitaLash Advanced
Best premium pick
RevitaLash Advanced Eyelash Conditioner
A physician-developed lash serum with the prostaglandin analog DDDE, biotin and peptides.
RevitaLash Advanced was created by an ophthalmologist, Dr. Michael Brinkenhoff, for his wife during her chemotherapy, and it remains one of the most respected names in lash serums. It uses DDDE, a different prostaglandin analog, along with biotin, peptides and green tea, ginseng and saw palmetto extracts.
Application is the same: one thin line along the upper lash line each night with a fine applicator.
The drawback is price. On Amazon, the 2 mL size costs about $100, nearly three times as much as GrandeLASH-MD, and there’s no published comparison showing it works better. It carries the same prostaglandin side effect risks.
Buy it if you prefer an established, physician-developed brand and don’t mind paying more for it.
Best Budget Pick: Babe Lash Essential Serum
Best budget pick
Babe Lash Essential Serum
A 1 mL starter size of a popular isopropyl cloprostenate lash serum, for trying one before you commit.
Babe Lash Essential Serum is the cheapest way to find out whether a prostaglandin serum works for you, and whether your eyes tolerate it. The 1 mL starter size costs about $29. Like GrandeLASH-MD, it uses isopropyl cloprostenate, plus conditioning ingredients. It has more than 23,000 Amazon ratings.
Babe’s directions are to apply a thin line to the upper lash line once a day, dipping the wand only once for both eyes. You can also use it on brows.
If it works for you, compare the per-milliliter price of the larger sizes before you reorder. Babe also sells a prostaglandin-free Renewing Lash Serum with peptides, which is a separate product; check the name before ordering.
Buy it if you want to try a prostaglandin serum for six weeks without spending more.
Best Prostaglandin-Free Serum: GrandeLASH-SENSITIVE
Best Prostaglandin-Free
GrandeLASH-SENSITIVE
A peptide, botanical and vitamin lash serum made without prostaglandins, for sensitive eyes.
GrandeLASH-SENSITIVE is Grande’s answer for people who can’t use or would rather avoid prostaglandin analogs. Instead, it uses a peptide blend Grande calls LashCatalyst, along with calming botanicals and vitamins. You apply it twice a day, morning and night, with a soft brush. Grande says lashes look thicker and longer, with less fallout, in about six weeks.
Set your expectations accordingly. Peptide serums haven’t been tested like prostaglandins, and you won’t get the dramatic length GrandeLASH-MD can deliver. What you should get is healthier-looking lashes that break and shed less, which is often what people with brittle lashes, or lashes damaged by extensions and curlers, actually need. The risks of eye irritation, darkened lids and eye color change mostly disappear.
Buy it if you have sensitive eyes, wear contacts, are pregnant or breastfeeding, have an eye condition, or just want a gentler serum.
When to Consider Latisse Instead
Latisse (bimatoprost 0.03%) is the only FDA-approved treatment for thin or short lashes, and it’s the most studied and generally the strongest option. It requires a prescription, which you can get from a dermatologist, eye doctor or an online telehealth service. Generic bimatoprost is available too.
It has the same side effects as cosmetic prostaglandin serums, but with known dosing, approved labeling and a doctor involved, which is a real advantage. It also makes sense if your lashes thinned because of chemotherapy, alopecia areata or another medical cause; see a doctor before treating lash loss that came on suddenly.
How to Use a Lash Serum
- Start with a clean, dry face at night. Remove makeup and contacts.
- Apply one thin stroke along the base of the upper lashes, where they meet the skin, like eyeliner. One stroke is enough. More product doesn’t speed results, but it does raise the risk of irritation.
- Skip the lower lash line. Serum spreads there when you blink.
- Blot any excess on the skin with a cotton swab, and wait for it to dry before applying anything else.
- Be patient and consistent. Lashes take six to 12 weeks to show results. Missing days slows them down.
- Stop if your eyes stay red or irritated, or if you notice changes in eye color or the skin around your eyes.
How We Chose
We sorted lash serums by active ingredient first, using brand-published ingredient lists, then compared price per milliliter, application directions, owner ratings and common complaints, and each brand’s track record. We checked the published research on prostaglandin analogs and peptide serums, along with the latest European safety review, and favored serums with clear labeling and directions.
For more eye-area care, see our guide to the best caffeine eye creams and our reviews of The Ordinary Caffeine Solution and La Roche-Posay Pigmentclar Eyes.
