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Over the last six months, Lt. Gov. Dan Patrick has built his case against THC products, claiming in press conferences, podcast episodes and social media posts, that the drug is proliferating without safeguards, driving young people to suicide, creating lifelong addicts, and altering users’ brains completely.

While THC users and industry groups have panned those claims as exaggerated, national experts say health concerns regarding THC products are not without merit.

Epidemiological and medical research conducted since the widespread legalization of THC across the United States has nuanced findings about THC’s safety, particularly with high-potency products and teenage users.

“It’s not black and white, it’s many shades of gray, right? But the risks are increasing. That’s for sure,” Dr. Deepak Cyril D’Souza, Director of Yale’s Center for the Science of Cannabis and Cannabinoids, who has studied these issues for 30 years, said.

Those scientists who sound the alarm about the adverse health effects of cannabinoids understand well the substance’s benefits in treating conditions like chronic pain and PTSD.

Still, they tend to call for public education about the risk of cannabinoids, age restrictions on use, and robust regulatory abilities for agencies that police the substance.

“Some of the reasons for the harms increasing are the lack of regulatory teeth for agencies to do really good lab testing and keep the legal market in shape,” said Dr. Ziva Cooper, director of the UCLA Center for Cannabis and Cannabinoids.

Patrick’s spokesperson Steve Aranyi told The Texas Tribune that the lieutenant governor’s claims are “well-settled issues,” referencing Texas Senate testimony on THC and a summary of a 2025 paper exploring links between habitual cannabis use and psychosis.

With Texas lawmakers returning to Austin on July 21 to try to rein in hemp-derived THC during a special legislative session, they will have to parse out noise from the truth. Here’s what scientists and drug policy analysts say about some of Patrick’s biggest claims.

Does “no one know” what is in consumable hemp products?

In press conferences, Patrick has repeatedly claimed that “no one knows” what is in consumable hemp products and that THC dosing disclosures are inaccurate.

Texas law requires consumable hemp products to be labeled with THC concentration and other ingredient information, enforced by the Texas Department of State Health Services.

Patrick has additionally claimed “we don’t know who is making these products,” going so far as to claim it could be terrorists or cartels. State law requires labels to include the name, telephone number and email address of the product’s manufacturer.

However, the issues that undermine these label requirements are two-fold, according to health experts.

A 2024 National Academies report noted “a great need to understand the health risks of emerging synthetic and semisynthetic cannabinoids.”

The health effects of some semi-synthetic compounds in hemp products like delta-8-THC and delta-10-THC are not yet understood by scientists. These compounds occur naturally in low dosages in the hemp plant, but modern manufacturing practices which rely on “strong acids and solvents” increase consumers’ exposure to them.

“Some of these semi-synthetics haven’t even been studied in an animal,” Cooper said.

In the absence of much research on these chemicals, most health claims about the effects of THC are based on scientists’ understanding of delta-9 THC, which occurs naturally in both cannabis and hemp.

Second, even if a label says there is a certain amount of THC in a product, that number may not be precise. Katharine Neill Harris, a drug policy fellow at Rice University, said the industry typically allows for some wiggle room in how much THC it says are in their products.

“You have a margin of error within 20%, so if a product claims to have 10 mg of THC, well, maybe it has 8 mg of THC,” she said. “It could maybe have 12 mg of THC, but there’s confidence that it’s within that margin of error.”

Are there specific harms for young people from THC?

Patrick frames his strongest critiques of THC around its impact on young people. “Nothing is more important than stopping a kid from getting ahold of this junk,” he told FOX 26 Houston in May.

Largely because their brains are still developing, teens are at a higher risk of nearly all of the adverse health effects of using THC products, from developing cannabis use disorder, to developing issues with memory and attention, research has shown.

“The later one starts using cannabis, the lower the risk,” D’Souza said, emphasizing that there is compelling evidence that use in mid-adolescence is more dangerous than using as a young adult.

According to the National Institute on Drug Abuse, heavy cannabis use in teens is associated with negative effects on memory and processing speed. The agency also links use of cannabis at a young age to other medical conditions including developing an addiction to it later in life.

Are products that contain THC addictive?

“Is cannabis addictive? No question about that,” D’Souza said.

The National Institute of Drug Abuse says risk factors for cannabis are similar to those of other potentially addictive drugs.

The prevalence of cannabis use disorder, a well-defined psychiatric condition that corresponds with overuse of the drug, has increased alongside the increased prevalence and potency of THC-containing products across the United States.

In 2023, 6.8% of people aged 12 and over and approximately 30% cannabis users, met the criteria for cannabis use disorder.

Does THC cause psychotic episodes?

Patrick frequently mentions the story of a 22-year-old who took a THC-infused hemp product and stepped in front of a train and died.

THC does, indisputably, trigger psychotic episodes in a small percentage of users. A widely-cited study of the subject published in The Lancet and referenced by multiple experts interviewed for this article found that while about 1% of the general population experiences a psychotic episode, about 5% of people who use high potency cannabis will experience one.

“That [still] means over 90% of people who smoke high-potency will be OK,” Sir Robin Murray, a psychiatrist at King’s College in London who contributed to the work, told NPR.

However, individuals who have a history of psychosis and psychological disorders should be discouraged from frequent use of these products specifically, Harris said.

“Using THC can exacerbate symptoms associated with schizophrenia. There’s some more limited evidence indicating that those who are genetically predisposed to schizophrenia or other psychosis-related mental illnesses that frequent use of THC products can increase the likelihood of those illnesses developing,” Harris said.

Though evidence is accumulating pointing to a relationship between cannabis use and long-term psychiatric disorders like schizophrenia the exact reason is unknown, according to D’Souza.

Does THC cause long-term brain changes?

Patrick said in a press-conference that these products, “could ruin your whole mental state for the rest of your life.”

The evidence here is mixed.

A 2017 review of over 10,000 studies found “moderate evidence” that extensive cannabinoid use impairs memory and attention.

D’Souza said whether THC causes irreversible changes to cognition is still debatable.

“Some studies suggest that, yes, there are long term consequences, and other studies suggest otherwise. So the jury is still out there,” he said.

Disclosure: Rice University has been a financial supporter of The Texas Tribune, a nonprofit, nonpartisan news organization that is funded in part by donations from members, foundations and corporate sponsors. Financial supporters play no role in the Tribune’s journalism. Find a complete list of them here.

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