Popular haircare company, Olaplex, is being sued by 28 women who claim its products caused hair loss, blisters and other conditions.
The Olaplex range includes shampoos, conditioners and treatments that claim to safely “repair broken bonds and rejuvenate hair”.
But the lawsuit says Olaplex uses harmful chemicals that left the women’s hair and scalps in a worse condition.
Olaplex has released test results that it says show the products are safe.
“We are prepared to vigorously defend our company, our brand, and our products against these baseless accusations,” it said in a statement on Instagram.
Olaplex has not recalled any of its products in the wake of the lawsuit.
Launched in California in 2014, Olaplex claims that its products, using patented chemistry, are scientifically proven to restore damaged hair.
It is particularly marketed towards people who bleach their hair, and while it is widely available to the public, several products are only sold to trained hair professionals. In many salons around the world it is offered – at an additional price – as a treatment for those getting their hair coloured.
The company has enjoyed massive success and has been endorsed by celebrities including Kim Kardashian and Drew Barrymore.
The lawsuit, filed last week in a Californian district court, claims the plaintiffs’ hair was left “dry, brittle, frizzy and dull”.
One woman said her hair became split and broken, making it look as if it had been cut using a “weedwhacker”.
Several photos of plaintiffs showing bald spots that they claim were caused by Olaplex have been released by the Law Centre of Amy E. Davis, one of the legal firms involved in the suit.
The plaintiffs are collectively seeking $75,000 (£62,200) in damages.
The lawsuit also claims that Olaplex products contain lilial and panthenol, chemical compounds that can lead to hair loss and conditions including “inflamed, blistered, flaking or scaling skin”.
Lilial was once used as a perfume in cosmetics, until the European Union banned it from March 2022 due to its impact on fertility.
Olaplex says it removed the ingredient from its products globally, “out of an abundance of caution”, however the lawsuit claims it is still selling the older products that contain lilial, also known as butylphenyl methylpropional.
The plaintiffs said they carefully considered any other factors that may have caused the women’s hair loss and scalp conditions, but found that “the products alone are to blame”.
Olaplex has strongly denied the allegations, insisting its range does “not cause hair loss or hair breakage”.
“Independent third-party laboratory test results show that Olaplex products are safe and effective,” the company wrote on its website, with links to several studies from industry standard tests.
The company’s CEO JuE Wong said on Twitter that hair loss was a painful and emotional topic “however for our products this is not true”.