Lawsuit Update Center
TRESemmé is a popular brand of shampoo and other hair care products made by Unilever, Inc. Consumers have filed lawsuits alleging that certain TRESemmé shampoo products contained chemicals that caused hair loss, thinning, scalp irritation, and other injuries.
About Unilever and TRESemmé
Unilever is a major manufacturer of personal care products and one of the leading shampoo manufacturers in the world. TRESemmé is one of Unilever’s most popular hair care brands. TRESemmé products are sold through major retailers and promoted through product labeling, advertising, and retail websites.
TRESemmé shampoo products previously contained DMDM hydantoin, a preservative that can release formaldehyde. Formaldehyde is a known human carcinogen and can also cause harmful effects when applied to the skin. TRESemmé lawsuits allege that Unilever failed to adequately warn consumers that some TRESemmé products contained DMDM hydantoin and other ingredients that could allegedly cause hair loss or scalp irritation.
July 31, 2026 Update- TRESemmé Hair Loss Lawsuit Dismissed as Untimely
A New York federal judge dismissed a lawsuit alleging that TRESemmé Color Revitalize shampoo caused hair loss, thinning, and scalp irritation. The plaintiff claimed that ingredients including DMDM hydantoin, MCI, and MI caused her hair to fall out in clumps and that the symptoms stopped after she quit using the products.
The case was dismissed because discovery revealed that a dermatologist told the plaintiff in January 2017 that TRESemmé might be causing her hair loss. Under New York’s three-year statute of limitations, she needed to file by January 2020, but she waited until December 2021.
This is a procedural defense win. The lesson for plaintiffs is that the filing deadline may begin when you first experience symptoms and a doctor identifies the product as a possible cause, even if the injury becomes much worse later. Waiting for hair loss to become severe can mean losing the case before a jury ever hears the evidence.
Frequently Asked Questions About the TRESemmé Lawsuit and Hair Loss Claims
What is the basis of the TRESemmé lawsuit?
The TRESemmé lawsuit alleges that certain TRESemmé shampoo products contained DMDM hydantoin, a preservative that releases formaldehyde. Plaintiffs claim that formaldehyde-releasing preservatives and other ingredients can cause scalp irritation, allergic reactions, thinning hair, and hair loss. Consumers argue that Unilever, the maker of TRESemmé shampoo, failed to properly warn about these risks.
Does TRESemmé shampoo cause hair loss?
Lawsuits claim that TRESemmé shampoo caused hair loss due to formaldehyde-releasing preservatives and other allegedly irritating ingredients. Unilever denies that its products are unsafe. Plaintiffs in TRESemmé hair loss lawsuits have reported hair thinning, breakage, scalp irritation, redness, inflammation, and clumps of hair falling out after using the products.
Has there been a TRESemmé class action lawsuit?
Yes. Multiple lawsuits, including proposed class action lawsuits, have been filed against Unilever over TRESemmé shampoo products. The litigation has produced mixed results. Some plaintiffs have pursued claims for hair loss, scalp irritation, and product refunds, while at least one New York case was dismissed in July 2026 because the plaintiff waited too long to file after a dermatologist identified TRESemmé as a possible cause of her hair loss.
Has Unilever changed the formula of TRESemmé shampoo?
Following concerns over DMDM hydantoin, Unilever announced in 2021 that it would reformulate its products to remove formaldehyde-releasing preservatives. As of July 2022, TRESemmé products sold in the United States no longer contain DMDM hydantoin. Unilever did not issue a recall, which means older products containing DMDM hydantoin may have remained in circulation for some time.
Is there evidence linking TRESemmé to cancer?
Concerns have been raised because DMDM hydantoin can release formaldehyde, and formaldehyde is classified as a known human carcinogen. But the TRESemmé lawsuits have focused primarily on hair loss, scalp irritation, allergic reactions, and alleged failure to warn. These lawsuits are not primarily cancer lawsuits.
Are other shampoo brands facing lawsuits for hair loss?
Yes. Shampoo lawsuits alleging hair loss and scalp irritation are not limited to TRESemmé. Several shampoo hair loss lawsuits have been filed against brands that contained DMDM hydantoin or other harsh preservatives.
- Unilever’s Suave Professionals Keratin Infusion line was recalled in 2012 following complaints of hair loss and scalp irritation, leading to a $10.2 million settlement in 2014.
- Johnson & Johnson has also been sued over its OGX shampoo products, which reportedly contained DMDM hydantoin. Consumers alleged that the company continued to use the ingredient despite knowing its potential risks.
- WEN by Chaz Dean faced a class action lawsuit in 2016, settling for $26 million after consumers reported hair loss and scalp irritation, though the specific ingredient causing these issues was not identified.
- Mielle Organics has come under scrutiny, with consumers alleging hair damage and loss, particularly after the brand’s acquisition by P&G Beauty in January 2023. Investigations are ongoing, and the company maintains that no formula changes have been made.
What damages were plaintiffs seeking in the TRESemmé lawsuit?
Individuals involved in TRESemmé lawsuits have sought compensation for:
- Medical expenses related to hair loss or scalp treatment
- Pain and suffering from emotional distress caused by hair damage
- Refunds for the cost of TRESemmé shampoo products
- Punitive damages against Unilever for allegedly misleading consumers about product safety
What should I do if I believe TRESemmé shampoo caused my hair loss?
If you suspect that a TRESemmé product caused hair loss, scalp irritation, or other adverse effects, you should:
- Discontinue use immediately and switch to a formaldehyde-free alternative
- Document your symptoms by taking photos and keeping track of hair loss
- Consult a dermatologist to assess scalp damage and potential treatment
- Preserve receipts, product bottles, photos, medical records, and the date you first suspected the product was causing symptoms
- Act quickly because the filing deadline may begin before the injury reaches its worst point
TRESemmé Hair Loss Lawsuit
Unilever has been sued by consumers alleging that they suffered hair loss and other injuries from chemicals in TRESemmé shampoo products. These lawsuits have focused on claims that certain TRESemmé products contained DMDM hydantoin, MCI, MI, and other ingredients that allegedly caused hair loss, thinning hair, scalp irritation, and allergic reactions.
The lawsuits allege that Unilever’s TRESemmé shampoo products were falsely and misleadingly marketed nationwide with labeling claims such as “deeply nourish,” “gently cleanse,” and “repair hair.” Plaintiffs argue that those representations did not match the risk of exposure to formaldehyde-releasing preservatives and other ingredients that could allegedly irritate the scalp or contribute to hair loss.
The litigation has produced mixed results. Some lawsuits have survived early pleading challenges, while others have been dismissed on procedural grounds. The July 2026 New York dismissal is a good example. The judge did not rule that TRESemmé could never cause hair loss. The case was dismissed because the plaintiff waited too long to sue after a dermatologist identified the product as a possible cause of her symptoms.
That distinction matters. A procedural dismissal is not the same thing as a defense win on the science. But it is still a real loss for that plaintiff and a warning to other consumers. If a doctor tells you a product may be causing hair loss or scalp injury, the statute of limitations clock may already be running.
While formaldehyde-releasers are commonly used in shampoo and conditioner to prevent microbial growth in water-based products, lawsuits argue that there are safer alternatives to DMDM hydantoin. Specifically, plaintiffs have cited the International Agency for Research on Cancer classifying formaldehyde as a human carcinogen and the National Toxicology Program of the Department of Health and Human Services identifying formaldehyde as a known carcinogen to humans.
The lawsuits also point out that many companies removed formaldehyde donors like DMDM from cosmetics and shampoos. Johnson & Johnson announced that it would remove potentially harmful chemicals, including formaldehyde, from its consumer products. CVS Health also announced that it would remove parabens, phthalates, and prevalent formaldehyde donors from its store-brand beauty and personal care products.
Consumers allege that Unilever failed to adequately warn customers about the use of DMDM in its products despite knowing about alleged side effects and risks to consumers’ hair and scalp. TRESemmé shampoo lawsuits have brought claims for manufacturing defect, design defect, failure to provide adequate warning, negligence, consumer protection violations, and related claims.
Alternatives to DMDM Hydantoin in Personal Care Products
Consumers looking to avoid DMDM hydantoin and its associated risks can choose products that use alternative preservatives such as sodium benzoate, phenoxyethanol, or other non-formaldehyde-releasing agents. Many companies have begun phasing out DMDM hydantoin and similar ingredients in favor of safer options. Reading product labels carefully and consulting databases like the Environmental Working Group’s Skin Deep database can help consumers make more informed choices.
Is DMDM Hydantoin Safe?
Regulatory bodies and industry specialists have maintained that DMDM hydantoin is safe in small amounts for regular use. But concerns persist, particularly for individuals who may be sensitive to formaldehyde exposure or other preservatives. Some jurisdictions, including California and Maryland, have taken steps to regulate products with excessive levels of formaldehyde. The lawsuits against DMDM hydantoin products reflect a broader demand for transparency and safer ingredients in personal care products.
Timeline of the TRESemmé Hair Loss Lawsuits and Related Events
July 31, 2026 – New York TRESemmé Lawsuit Dismissed as Untimely
The ruling is a reminder that a hair loss lawsuit can be lost before a jury hears anything about product safety. If a doctor connects symptoms to a product, even only as a possible cause, that may be enough to start the limitations clock.
2024 – 2026: Ongoing Litigation and Procedural Fights
- Concerns about TRESemmé hair loss continued, but the litigation has not produced a major public global settlement.
- Some cases continue to focus on product ingredients, warnings, and alleged hair loss, while others have run into procedural defenses such as statutes of limitations.
- Our law firm is not handling these lawsuits, but we continue to get calls from frustrated consumers looking for somewhere to turn.
2021 – 2023: Legal Battles Continue
- Additional lawsuits and class action claims against TRESemmé shampoo continued, with consumers seeking compensation for damages.
- Legal experts analyzed whether Unilever’s failure to recall older TRESemmé products could increase liability in ongoing and future lawsuits.
- Plaintiffs argued that Unilever had knowledge of DMDM hydantoin’s risks for years but failed to act until legal pressure mounted.
July 2021 – Unilever Removes DMDM Hydantoin
- Unilever announces it will remove DMDM hydantoin from all of its U.S. hair care products, including TRESemmé shampoo.
- Despite reformulating its products, Unilever does not issue a recall for previously sold products containing DMDM hydantoin.
May 19, 2021 – Major Lawsuit Filed
- Plaintiff files a lawsuit in the U.S. District Court for the Eastern District of New York against Unilever United States, Inc.
- The TRESemmé lawsuit alleges negligence, manufacturing defects, design defects, and failure to provide adequate warnings.
- The complaint cites past litigation, online consumer complaints, and research showing that DMDM hydantoin is linked to dermatitis, allergic reactions, and hair loss. The lawsuit argues that Unilever knowingly sold a harmful product despite safer alternatives being available.
2020 – Lawsuits Begin
- A soon-to-be class action lead plaintiff purchases TRESemmé shampoo and experiences hair loss, scalp irritation, and thinning hair.
- After noticing severe hair loss, she discontinues the use of TRESemmé products.
- Other lawsuits are filed against Unilever, alleging that TRESemmé shampoo causes hair loss and that the company failed to warn consumers.
2013 – 2020: Consumer Complaints Grow
Other cosmetic companies, such as Johnson & Johnson and CVS, remove DMDM hydantoin from their shampoos and beauty products due to safety concerns.
Despite growing concerns and lawsuits against formaldehyde-releasing preservatives, Unilever continues using DMDM hydantoin in some TRESemmé products during this period.
2012 – Initial Lawsuits Filed
Unilever recalls the Suave Keratin Kit following customer complaints.
Unilever ultimately settles the lawsuits, agreeing to pay $10.25 million in damages.
Hiring a Lawyer for Your Claim
Our law firm is not currently handling lawsuits related to TRESemmé products or DMDM hydantoin. However, we believe in empowering consumers with information to help them make informed decisions about their rights and the products they use.
This page was created to provide a comprehensive overview of the allegations and concerns surrounding TRESemmé products and the potential risks of certain ingredients, such as DMDM hydantoin. Our lawyers recognize the importance of transparency in the personal care industry and aim to equip consumers with knowledge about ongoing litigation, product safety, and alternatives.
If you have been impacted by issues related to TRESemmé or similar products, we encourage you to consult with an attorney who handles product liability or consumer protection cases. While we are not currently representing clients in these lawsuits, we will continue to update this page with relevant information as it becomes available.
