Marijuana can often help with autism symptoms, but it's complicated. A new study indicates why

Autistic people who smoke marijuana often report having positive experiences. Yet their anecdotal evidence does not in and of itself prove that marijuana is an effective drug for treating autistic symptoms. To help fill that void, a recent study published in the journal Frontiers in Psychiatry examined 20 patients with autistic symptoms who had been treated with full-spectrum cannabis extracts (FCEs).

Although the study concluded that marijuana largely helps autistic people address their core symptoms, the study's corresponding author painted a more complicated picture about if and how autistic people can safely consume cannabis. Much of it comes down to ratios of two drugs found in marijuana: THC (tetrahydrocannabinol), the drug that gets people high and CBD (cannabidiol), a non-intoxicating compound sought for its medicinal properties.

"The outcomes were mainly positive for most symptoms," the authors reported, noting that the two exceptions included a patient who was only medicated with CBD-rich FCE and another who was medicated with a blend of CBD-Rich and THC-rich FCEs. "After FCE treatment, 18 out of 20 patients showed improvement in most core and comorbid symptoms of autism, and in quality of life for patients and their families," the authors concluded. "For them, side effects were mild and infrequent."

Dr. Renato Malcher-Lopes, the corresponding author of the study, told Salon that because there is such a wide variety of autism spectrum disorders, it would be misleading to say that their study found marijuana "treats autism." It would instead be more accurate to say that there are core symptom domains of autism — defined in the study as "restricted or repetitive behaviors and impairment in language/communication and social skills" — and that these, not "autism" as a monolith, were specifically studied.

"There is a collection of symptoms that goes under the umbrella Autism Spectrum Disorder," Malcher-Lopes, who works at the University of Brasilia's Laboratory of Neuroscience and Behavior, explained. "You have the core symptoms, which minimally qualify someone as autistic, but rarely does a person only have the core symptoms. It's very common for people to have co-morbidities in different levels of severity."

These can include difficulty with emotional self-regulation, intellectual impairments, behavioral deficits and eating non-food substances. In every patient's situation, it is critical to think of how marijuana will impact each of those symptoms, both individually and as a cluster. That will often vary significantly from patient to patient, but this study adds to the body of research suggesting cannabis can improve quality of life for autistic people.

At the same time, Malcher-Lopes pointed out that there was a common theme in his research.

"One thing that's very important, we make sure in our protocol that everybody receives a lot of CBD [cannabidiol]," Malcher-Lopes told Salon. "Why is that? Because CBD is an anti-inflammatory substance. It also has some effects that reduce the excessive synaptic activation, and this is good because it creates some kind of ceiling for the level of hyper-activation the nervous system might have. And by doing that you reduce the risk of seizures, the risk of anxiety, hyper-activity, etc."

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Malcher-Lopes also warned against autistic people using excessive amounts of THC, which he notes has been traced to adverse effects in many autistic patients.

"If you use THC alone, THC has an effect that CBD does not have, which is to cause euphoria," Malcher-Lopes began. "If you start increasing the dose, you'll increase the dose of euphoria. But if you then keep increasing it, you'll feel very anxious."

But it's not always easy to assess the THC and CBD levels in marijuana products. Some products are mislabeled or test results are sometimes inflated or distorted.

"It's tricky," Malcher-Lopes explained. "The key problem here is the proportion between the THC and CBD. I would say that it's advisable for everybody to be advised by a physician."

Scientists generally agree that both cannabis and cannabinoids "may have promising effects in the treatment of symptoms related to ASD [autism spectrum disorder], and can be used as a therapeutic alternative in the relief of those symptoms," although there have not been enough "randomized, blind, placebo-controlled clinical trials" to prove that.

Malcher-Lopes's study acknowledges this, with the authors explaining that because "the endocannabinoid system plays a key role in ASD," there have recently been a number of studies of cannabinoid treatment in humans that wound up showing "some improvements in most core ASD symptoms, as well as in several comorbid symptoms, and infrequent mild side effects."

These benefits may be linked to the fact that THC and CBD bind themselves to proteins in the brain and body known as cannabinoid receptors. Taken individually, they can have different effects. Taken together, they can produce a sort of synergistic effect, because CBD is a negative allosteric modulator, meaning it can change how THC binds to these receptors, though this complex relationship is often oversimplified.

Regardless, finding a balance with cannabis seems to benefit many people. Autistic people in particular will talk anecdotally about the benefits of using marijuana. Speaking to Salon last year, Russell Lehmann, an autistic contributor to Autism Parenting Magazine, said that "I personally function at a much higher level with this plant in my life than I do without it. I also don't smoke to escape reality but rather to process reality. We really need to engage in more open dialogues about this plant as there are many misconceptions out there that are preventing certain individuals from discovering the potential benefits."

Similarly Joann Fouquette, who in December talked to CNN about how CBD helped her young autistic son Ezra, told that network's Dr. Sanjay Gupta that the drug "it helped him ... whatever is going on in his brain, make those connections that he needed to make. And once those connections were made, he never lost them."