UC San Diego team sets out to study the effects of cannabis component CBD on severe autism in children

Study coordinator Caitlin Knight (left) and principal investigator Dr. Doris Trauner
Study coordinator Caitlin Knight (left) and principal investigator Dr. Doris Trauner review an MRI scan of a child with autism as part of a UC San Diego study of the effects of CBD on autism.
(Courtesy of Caitlin Knight)

UC San Diego researchers are looking for participants for a clinical trial to study the effectiveness of cannabidiol, or CBD, in treating symptoms of severe autism in children.

Cannabidiol is a chemical compound found in cannabis. CBD does not contain THC, the psychoactive ingredient in marijuana that produces a high.

CBD oil has been approved by the U.S. Food and Drug Administration as an epilepsy medication, and the chemical has been studied as a treatment for several other conditions.

The goal of the UCSD study “is to determine whether CBD reduces the problem behaviors that we see in children with severe autism,” said the study’s principal investigator, Dr. Doris Trauner, a pediatric neurologist and professor of neuroscience at UCSD’s School of Medicine.

Trauner said the behaviors the study will target “are specifically aggressive behaviors, self-injurious behavior [and] persistent repetitive behaviors, what are called stereotypic behaviors,” such as shaking or other repetitive movement that “interferes with their ability to function.”

“What we’re trying to identify is whether CBD reduces the problem with behaviors and then, in turn, whether that could improve their ability to function,” Trauner said.

The study is looking for 30 boys ages 7-14, with a second phase for girls planned for later.

Separating girls from boys is important, Trauner said, as “boys are identified four times more commonly than girls as having autism or autism spectrum disorder [and] girls have different symptoms than boys do.”

She said it’s possible autism is more common in girls, “but it’s missed because the symptoms are different. The feeling was that if we did a study that included boys and girls together and looked at the same endpoints, we might not see what the benefit would be because I think there are different endpoints for the girls than there are for the boys.”

Trauner said studying boys and girls separately will enable her to design studies that might improve behaviors particular to each gender.

The center brings together nine fields of science to study pregnancy and early childhood.

During the study, participants will be given either CBD or a placebo to take orally every day for eight weeks. The study is double blind, meaning neither Trauner nor the children or their parents know whether they’ve been given the placebo; that information is known only to the study’s research pharmacist.

The participants then will have a four-week break, “a washout period to clear whatever was in their system,” Trauner said, after which they will “cross over,” meaning they will be given either the CBD or placebo — whichever they didn’t receive the first eight weeks — for eight more weeks.

“Everyone will be taking CBD, but they won’t know when,” Trauner said.

Before the participants are given anything, they will undergo several tests, she said, including an autism diagnostic screen to determine the severity of the autism, plus language testing and a nonverbal IQ test.

“We also then do an MRI scan of the brain,” Trauner said, which includes a “magnetic resonance spectroscopy, where we look at certain brain chemicals.”

Parents will be asked to fill out questionnaires about their children’s behavior, she said.

Trauner said she hopes to find that CBD helps to reduce aggressive behaviors, anxiety, hyperactivity and repetitive behaviors “to allow the children to be more socially available.”

During the study, the children will receive regular medical exams, electrocardiograms and blood tests to ensure “they’re not getting any toxicity from anything,” she said.

The strict parameters and frequency of medical testing also will help Trauner and her team watch for side effects from CBD, which “is not a benign drug,” she said. People can mistakenly believe that because it is plant-derived, “it must be safe,” she added.

CBD can cause changes in appetite and behavior, stomach upset and liver damage if not used properly, Trauner said.

The few drugs approved to treat severe autism come with their own, often harsh side effects, Trauner said, and “parents rightly are concerned about using medication like that for a long time because a lot of children need it for years.”

“I’m really excited about the study,” she added. “If we can show that for the majority of children it has a significant benefit, it would be a whole new area [of] very exciting treatment.”

Parents interested in the study can email study coordinator Caitlin Knight at or call (858) 822-6701. ◆