The manufacturer of the popular hair-straightening product Brazilian Blowout, the subject of government inquiries and health complaints, said on Monday that it had agreed to settle a class-action lawsuit for about $4.5 million. 

Under the terms of the agreement, consumers who contend they were harmed by the product would receive a $35 payment for each treatment, up to three total, and stylists would receive $75 for each bottle of the product they bought, said Elizabeth Pritzker, a lawyer for the plaintiffs. 

In addition, Brazilian Blowout can no longer market its product as “formaldehyde free,” and the company must provide more detailed instructions on how to use it safely, she said. 

“They can still sell the product as long as they market it appropriately,” Ms. Pritzker said. “Our major concern is that people simply know what it is that they are buying.” 

The proposed settlement goes before Judge Elihu Berle of Los Angeles Superior Court on Tuesday for approval. 

Earlier this year, Brazilian Blowout, which is based in North Hollywood, Calif., agreed to pay $600,000 in fees and penalties in a settlement with the California attorney general’s office in which it agreed to warn consumers that its product emits formaldehyde gas. The federal government listed formaldehyde as a carcinogen last year. 

Michael Brady, Brazilian Blowout’s chief executive, said the proposed settlement would be paid by his insurance company and would end an unpleasant episode for his company. “We get to sell the product forever without reformulation,” he said. “In my eyes, that’s the acquittal we’ve been waiting for.” 

Mr. Brady said his product posed no issues for stylists or consumers as long as it was used correctly in a well-ventilated area. 

“We just want people to treat it like they do aspirin — make sure you only use it as directed,” he said.
In 2010, regulators in Canada and Oregon issued warnings about Brazilian Blowout after complaints from stylists that it was causing nosebleeds, breathing problems and eye irritation. The product uses amino acids and methylene glycol to straighten frizzy hair; when heated, it emits formaldehyde gas. The product is not sold directly to consumers, but to stylists; a treatment takes about 90 minutes and costs about $300. 

Last year, the Food and Drug Administration issued a warning letter to Brazilian Blowout because it emitted formaldehyde gas and was mislabeled as formaldehyde-free. An F.D.A. spokesman said on Monday that its inquiry into Brazilian Blowout was continuing.