Hair today, gone tomorrow.

More than 200 women in 40 states have joined a class-action lawsuit against the makers of the hair care line WEN, claiming that the products can cause severe hair damage — including bald spots and rashes, according to a report.

The class-action lawsuit against celebrity hairstylist Chaz Dean and direct marketing company Guthy-Renker, which markets the product, was filed in California Federal Court, according to The Daily Beast.

Multiple lawsuits have been filed against WEN in recent years, but the size and scope of the class-action lawsuit has drawn new attention to customers’ hair-raising hair loss claims. An online questionnaire is available for those affected by their use of WEN hair products.

Tracie Hashton via Facebook

WEN customers have posted claims online that the hair care products have caused them to lose their hair.

WEN customers have posted claims online that the hair care products have caused them to lose their hair.

One of the plaintiffs, Amy Friedman of Florida, has stated that she purchased a WEN Cleansing Conditioner Sweet Almond Mint basic kit for $29.95 — and soon noticed a problem.

“Within two weeks of beginning use of her WEN Cleansing Conditioner, Plaintiff began losing substantial and abnormal amounts of hair,” legal filings state.

Numerous people have also shared complaints online. One woman posted an image on WEN’s Facebook page showing a bald spot, claiming that the products “caused my hair to be basically washed with lotion,” she wrote. She stated that she cries when she looks in the mirror, and was forced to wear a baseball cap when she goes outside.

Other customers wrote reviews on the site “Pissed Consumer,” a consumer complaints website.

WEN by Chaz Dean

The WEN hair care line was developed by celebrity hairstylist Chaz Dean.

The WEN hair care line was developed by celebrity hairstylist Chaz Dean.

“I had been using WEN for five months when I noticed a bald spot the size of a half dollar at the crown of my head.. I nearly passed out,” the person wrote.

WEN hair care has been accredited by the Better Business Bureau since 2008 and currently holds an A+ rating. More than 750 complaints against WEN hair care were closed in the last three years, including 270 in the last year, the BBB states.

Some of the BBB complaints against WEN hair care involve hair loss problems, records show.

WEN by Chaz Dean

Alyssas Milano is among the celebrities who have appeared in WEN ads.

Alyssas Milano is among the celebrities who have appeared in WEN ads.

“WITHIN A FEW DAYS MY HAIR WAS STARTING TO FALL OUT,” one customer wrote in July. “AT FIRST I DID NOT THINK IT WAS FROM THE PRODUCT. AFTER A WEEK OR SO IT SEEMED TO BE GETTING WORSE. I ACTUALLY WENT TO MY DOCTOR THINKING SOMETHING MEDICAL WAS GOING ON. HE DID A BLOOD TEST FOR ME.”

The company later refunded the customer their money, records show.

WEN’s website states that its hair care products will “give your hair more shine, body and bounce.”

The hair care line has been hugely popular, generating hundreds of millions of dollars in sales, according to Forbes. Commercials for WEN’s products have featured such celebrities as Brooke Shields and Alyssa Milano.

WEN by Chaz Dean

Brooke Shields has appeared in WEN ads.

Brooke Shields has appeared in WEN ads.

The popular products have garnered four-star ratings on Amazon.com, but some customers state that there are two different versions of WEN products — those distributed by Guthry-Renker, and those sold online.

“I could tell a difference IMMEDIATELY,” one user wrote on Amazon.com. “The product was not sliding through my hair easily, it seemed almost sticky. Then, when I rinsed my hair, it felt dried out and rough, and when it dried, it looked greasy and brittle.”

A spokesperson for the company defended WEN’s hair care line and stated that no specific cause for the hair loss has emerged.

“We take great pride in the quality of our products and believe every product meets our high standards. We want all of our customers to have positive experiences with our products, and we encourage any customer with any questions to contact us,” Joe Hixson said in a statement. “Importantly, there is no scientific evidence whatsoever to support any claim that our hair care products caused anyone to lose their hair. There are many reasons why individuals may lose their hair, all unrelated to WEN hair care products. We will vigorously contest the allegations made against our products.”

Attorney Amy Davis, lead counsel for the victims, told The Daily Beast that the sides are headed to mediation.

“The parties are attempting to settle their differences outside of court and we have agreed to refrain from any extrajudicial statements about the case in the meantime,” she told The Daily Beast.