THC More Effective Than CBD In Treating Autism, New Preliminary Study Shows
As cannabis becomes less stigmatized, the autism community is exploring treatments that are more accessible and less pharmaceutical.
So far, a number of studies have confirmed that medical cannabis helps alleviate behavioral problems in children with autism.
The Journal of Autism and Developmental Disorders, for example, found that the use of cannabidiol-rich cannabis improved behavioral outbreaks in 61% of patients in a study of 60 children on the autism spectrum.
An Israeli study, published in Nature in 2019, proved the same. A total of 188 patients with the same condition had been treated with an oil containing 30% CBD and 1.5% THC between 2015 and 2017. The oil appeared to be “well-tolerated, safe and effective.”
THC More Effective Than CBD
However, Israeli scientists took it a step further, suggesting that THC is the more promising cannabinoid than CBD to treat the disorder.
Researchers said in a new study, published in October, that cannabis is poised to change the direction of autism treatment.
After studying a large mouse model for autism, Tel Aviv University researchers came to the conclusion that tetrahydrocannabinol (THC) may be more effective than CBD.
Researcher Shani Poleg told The Times of Israel that the studies currently underway “mostly don’t focus enough on the details of what it is in the cannabis that may be helping people.”
Poleg added that THC was more effective in her comments on the results of preliminary research, supervised by Prof. Daniel Offen and recently peer-reviewed and published in the journal Translational Psychology.
“The main difference was that THC treatment also improved social behavior, not only repetitive, compulsive behavior,” she said.
Poleg explained that the cannabis oil given to the mice contained small amounts of THC.
“We observed significant improvement in behavioral tests following treatments with cannabis oil,” she said, adding that there were “no long-term effects in cognitive or emotional tests conducted a month and a half after the treatment began.”
However, the mutation that caused autism in Poleg’s mice is found in a small minority of human autism cases.
“But we hope that this may have the effect of both encouraging further exploration of medical cannabis use for autism and lead to a better type of cannabis being used,” Poleg concluded.
Real Life Experience of Medical Cannabis Treatment in Autism: Analysis of Safety and Efficacy
Bar-Lev Schleider, L., Mechoulam, R., Saban, N., Meiri, G., & Novack, V. (2019). Real life experience of medical cannabis treatment in autism: Analysis of safety and efficacy. Scientific Reports, 9, 1-7. doi:10.1038/s41598-018-37570-y
Reviewed by Nyasia Sanchez, Masters Candidate, and Frank R. Cicero, PhD, BCBA, LBA, Assistant Professor, Seton Hall University
Why research this topic?
There has been some recent literature suggesting that CBD-enriched cannabis has beneficial effects for individuals with autism spectrum disorder (ASD). Cannabidiol (CBD) is a natural compound found in the cannabis sativa plant. Unlike tetrahydrocannabinol (THC), another compound also found in the cannabis sativa plant, CBD is not associated with the sensation of a “high” or hallucinations when ingested (https://www.healthline.com/health/cbd-vs-thc#chemical-structure). Bar-Lev Schleider et al. (2019), cite past research indicating that CBD may alleviate symptoms of psychosis and anxiety, facilitate REM sleep, and suppress seizures. In 2014, the Israeli Ministry of Health approved the use of CBD-enriched cannabis for the treatment of epilepsy. Parents of children with autism began to seek CBD-enriched cannabis after seeing reductions of anxiety, aggression, panic, tantrums, and self-injury in children with epilepsy receiving the treatment. Although there may be some preliminary evidence of the beneficial effects of CBD treatment for children with ASD, there is a lack of research regarding specific symptoms that are likely to respond to treatment as well as a lack of knowledge regarding safety precautions when using CBD-enriched cannabis with this population.
What did the researchers do?
The purpose of the study was to investigate the general effectiveness and side effects of cannabis treatment with children with ASD. Participants consisted of 188 children with a diagnosis of ASD established per diagnostic standards in Israel. Mean age at start of treatment was 12.9 years with a range of <5 to 18 years. Out of the 188 participants, 27 had a comorbid diagnosis of epilepsy and seven had a comorbid diagnosis of attention deficit hyperactivity disorder. At intake, the use of antipsychotic medications was reported by 56.9% of participants, antiepileptics by 26% of participants, hypnotics and sedatives by 14.9% of participants, and antidepressants by 10.6% of participants. Use of these medications continued throughout the study as needed. A range of pre-existing symptoms was noted in baseline, the most common being restlessness (reported by 90.4% of participants), rage attacks (reported by 79.8% of participants), and agitation (reported by 78.7% of participants). For the majority of participants, treatment consisted of the application of cannabis oil under the tongue, three times per day. The oil consisted of 30% CBD and 1.5% THC on average. A small percentage of participants received slightly modified treatment regimens (i.e. different dosage, different CBD/THC ratio, taking additional doses of CBD for conditions such as insomnia, etc.). Parents of participants completed symptom questionnaires after one and six months of treatment.
What did the researchers find?
Of the 188 original participants, 179 continued with active treatment. At one month follow up, 119 participants completed symptom questionnaires. Data at one month indicated that 48.7% of participants reported significant improvement, 31.1% moderate improvement, and 14.3% no improvement. The presence of side effects was reported by 5.9% of participants. The most common reported side effects at one month included sleeplessness, bad taste and smell of the oil, restlessness, reflux, and lack of appetite. After six months, 155 participants were still in active treatment with 93 completing the symptom questionnaire. Data at six months indicated that 30.1% reported significant improvement, 53.7% moderate improvement, 6.4% slight improvement, and 8.6% no improvement. Reports indicated an improvement in restlessness in 91% of participants and an improvement in rage attacks in 90.3% of participants. The presence of side effects at six months was reported by 25.2% of participants, with the most common side effects being restlessness, sleepiness, psychoactive effects, increased appetite, digestion problems, dry mouth, and lack of appetite. In addition to the symptom questionnaire, reports of “quality of life” and the ability to complete activities of daily living were collected at baseline and at six months. Results indicated statistically significant improvements in “quality of life,” “positive mood,” independent dressing, independent showering, sleeping, and concentration. Improvements were also noted in seizure activity. Out of 13 participants with a diagnosis of epilepsy, 11 reported the disappearance of seizures at six months of treatment, and an additional two reported decreases in seizure activity.
What were the strengths and limitations of the study? What do the results mean?
According to the authors, results of the study show that CBD-enriched cannabis treatment of ASD can potentially lead to improvements in behavioral symptoms. This is consistent with the results of some studies showing improvements in participants with anxiety disorders and other conditions when CBD-enriched treatment was initiated. The authors state that the treatment appears to be safe, well tolerated, and accompanied by notable, yet only minor side effects.
There are, however, a number of significant limitations with the study design and procedures that indicate the need for caution when interpreting the results. First, the study did not contain a comparison control group, therefore no causality between cannabis treatment and behavioral improvement could be established. This indicates that, although improvement was reported in behavioral symptoms, the data may be reflecting the effects of something other than the cannabis treatment. Second, parents seeking cannabis treatment may not represent the majority of families with a child with ASD. It is important to note that 10% of participants reported that they had already used cannabis treatment prior to the present study. This self-selection bias could have affected the results. Third, ASD diagnoses were not confirmed at the time of the study, therefore accuracy in diagnosis cannot be confirmed. Fourth, results were based on subjective completion of questionnaires by parents. Objective measures of behavioral improvement, based on direct observation, were not used. This could have inflated positive results due to parent expectations. In addition, terminology used in the rating scales were sometimes vague and not well defined. Fifth is the limitation of concomitant use of other medications for behavioral and medical treatment. The effects of these medications cannot be teased out from effects of the cannabis treatment. Sixth is the slight variations in treatment regimens and the lack of oversight over treatment fidelity. The final limitation is the large attrition rate from intake to follow up. Out of the 188 participants that started treatment, only 93 participants (49%) remained with the study to the follow up survey.
What do the results mean?
Results indicate that cannabis as a treatment for ASD may potentially be a well-tolerated, safe, and effective option for the treatment of some ASD symptoms including improvements in seizures, tics, depression, rage attacks, and restlessness. Improvements may also be obtained in quality of life and independence in daily living. We do not yet, however, know the mechanisms by which cannabis treatment may show these effects. Unfortunately, a number of significant limitations with the study design prevented a causal relationship from being established between cannabis treatment and behavioral reports. Results having been based on subjective measures are also problematic. Therefore, the results of the current study, although promising, can be considered preliminary at best. The authors suggest that a call for a double-blind, placebo-controlled clinical trial is indicated. In the meantime, extreme caution and professional consultation should be used when considering cannabis treatment for individuals with autism.