A maker of cannabis and herb supplements in Adams County recently settled one lawsuit and faces other claims after some people who took its marijuana-infused sleep aids said they developed sudden liver problems.

Bailey Pate, a 36-year-old resident of the Denver area, sued Sima Sciences and Nuka Enterprises, both based in Henderson. She alleged that their “Midnight” sleep aid drops caused liver damage after she used them for about 16 months in 2020 and 2021.

She settled with the companies this week for an undisclosed amount.

Laura Browne, an attorney who represented Pate, said thousands of people in Colorado and a handful of other states may have claims, either for injuries they suffered or for the money they spent on a potentially unsafe product.

The drops, sold under the 1906 brand name, included cannabis and corydalis, a traditional Chinese herbal remedy. Corydalis contains tetrahydropalmatine, or THP, a chemical that can cause liver damage at high doses. The manufacturers recalled the products earlier this year.

Peter Barsoom, the CEO of Nuka Enterprises, told The Denver Post in a statement Wednesday that the company “received a small number of reports from customers” who experienced a rare side effect — elevated liver enzymes — from the drops in their latest formulation.

“In every case we are aware of, levels went back to normal after discontinuing use,” he wrote. “While thousands used Midnight every night without any side effects, we take our responsibility seriously and discontinued Midnight earlier this year. We deeply regret the suffering that some customers experienced.”

In July 2022, the Marijuana Enforcement Division and the Colorado Department of Public Health and Environment issued a warning that said the products could cause liver injury. The drops remained available for sale, however, because the manufacturers said they had replaced corydalis with stephania, another herb.

Another state announcement in June said the manufacturers were working to remove the drops from store shelves after reports of liver injuries from the stephania version. The Marijuana Enforcement Division routinely accepts complaints about harm from marijuana products investigating them with the state health department if the alleged health consequences are serious.

Evan Hoffman, a Denver lawyer, said he represents about 30 people who developed liver problems after using the drops. About half of his clients were hospitalized, usually between two and eight days, after developing jaundice, nausea and unexplained fatigue, he said.

His clients are in settlement talks with the company, and some others have reached their own settlements, Hoffman said. He estimated two to four people still reach out to him in a typical week as they realize what could have caused their sudden liver problems, he said.

“People are still just now putting the pieces together,” he said.

Hoffman said his clients are not only upset about the unknown health consequences of their liver damage but angry that the company seemed to know it was a possibility and didn’t warn them.

“They didn’t do anything about it because it was their best-selling product,” he said.

As of late November, the manufacturers were selling six other products under the 1906 label. Visitors to the site could click on a list of ingredients, but the only warnings stated that customers should consult their doctors about any dietary supplements, and that pregnant and breastfeeding women shouldn’t take these products.

Online searches for the ingredients turned up some that were linked to kidney damage and liver failure. Others could worsen autoimmune diseases or interfere with medications. Plant-based remedies generally aren’t studied extensively, however, so it’s not clear if the amount of herbs in the supplements could be dangerous.

The U.S. Food and Drug Administration doesn’t regulate supplements unless they state the product can treat, prevent, diagnose or cure a specific condition. That’s why so many products make nebulous claims, such as that they “boost immunity.”

Browne said the absence of meaningful regulation means that “you really need to take it upon yourself … to investigate the ingredients as much as you can.” She added: “But consumers shouldn’t have that put on them.”

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