The long claims behind longer eyelashes

Lash serums can have risky side effects when used.

When an eyelash growth product called Lavish Lash became an Amazon best seller in 2017, a flood of customers promptly wrote to ask: Can I use this on my eyebrows?

Answer: Yes. But then, inevitably, the product’s maker, a Miami company called Hairgenics, released an eyebrow-specific formula. Asked about the key difference in the new product, Mark Transky, the president of the company, said in an interview: “It’s about 15% stronger.”

Then he laughed and said, almost ruefully, “Now people are going to use this one on their lashes.”

Such is the desperation for doe eyes and big brows that it seems customers (mostly women) will try almost anything. “There has been a cultural infatuation with brows for some time, along with an increased interest in glowing skin and big lashes,” Dave Kimbell, the president of the Ulta Beauty cosmetic chain, wrote in an email.

It’s a trend that shows little sign of stopping, he said. Besides the many offerings by niche companies like RapidLash, legacy brands like L’Oréal and Maybelline have recently released lash serums.

But what really does work? For actually growing hair, not very much.

This is partly because, compared with the hairs on your head, both lashes and brows have supershort growth phases, so it’s tough to catch them then, when they’re treatable.

“You wouldn’t want to yank out

all your eyelashes just to get them all to start growing at the same time,” said Angela Christiano, a hair geneticist and a professor of dermatology at Columbia University.

For lashes, there is still only one product proven effective: Latisse, the brand name for a prostaglandin called bimatoprost. The 11-year-old prescription drug, made by Allergan, continues to be popular, in spite of its risks. Besides dry and itchy eyes, side effects include permanent darkening of the skin around the eye and of the iris itself (like from blue to brown).

Users may also see drooping of the upper eyelid and shrinking of the fat pad beneath the eye. (The shrinking may not be a bad thing if you have puffy eyes, but it can make your eyes look sunken if you have deepset ones.)

There are also over-thecounter potions made with analogues of prostaglandins — often isopropyl cloprostenate, dechloro dihydroxy difluoro ethylcloprostenolamide or methylamido dihydro noralfaprostal on ingredient lists. These are very likely to work, said Maryanne Senna, a dermatologist and the director of the Hair Academic Innovative Research Unit (get it? HAIR) at Massachusetts General Hospital in Boston.

But, she said, “the likelihood of them causing the same problems as Latisse is real.

“That’s my big fear with people buying them, that they won’t be informed about the risk,” Senna said. (She does prescribe Latisse, though only after a rundown of potential drawbacks.)

A pending federal classaction suit against Rodan + Fields, the maker of the popular Lash Boost (which contains isopropyl cloprostenate), accuses the company of deceptive marketing and said it “failed to disclose the harmful side effects linked to an ingredient.”

A second-class action suit, as well as a personal injury lawsuit, are also pending. Rodan + Fields had no comment.

With any of the prostaglandins, you will need to keep using them or your lashes or brows will go back to whatever they were originally — or, if you have been using the products for years, possibly worse, because of agerelated thinning.

Anything without a prostaglandin, no matter how impressive or scientific sounding the ingredients, is unlikely to make lashes grow. Most beauty products in this arena, including ones costing upward of $100, contain “completely inactive bogus ingredients,” said Senna, who is also an assistant professor of dermatology at Harvard University. (Somewhat tellingly, no doctor interviewed had specific products to recommend.)

What serums like Lavish Lash do, and what may prompt the thousands of fivestar reviews, is make lashes look fuller and thicker by coating them with film, said Perry Romanowski, a cosmetic chemist and a founder of thebeautybrains.com, a site where scientists examine product claims.

Romanowski scoffs at myths companies spin around ingredients like horsetail root and sweet almond protein, saying results actually come from prosaic things like hydroxyethylcellulose, a gelling and thickening agent often found in plain old-fashioned (and much cheaper) mascara.